fs25...service notes iii service notes this service manual describes the service and repair...

FS25

ASM-0002E SERVICE MANUAL

May 2019

Front Non-Drive Steer Axles

Table of Contents

ii

Table of ContentsService Notes ..................................................iii

Asbestos and Non-Asbestos Fibers Warning ...... iv

Service Precautions ......................................... viTowing ............................................................ viRepair Warnings ............................................. viiTorque Specifi cations ..................................... viiCleaning ........................................................ viiDamaged Components ................................... viiRepair Welding .............................................. viiiOmissions ..................................................... viii

General Assembly Instructions ......................... ixTapered Roller Bearings .................................. ixCastings ......................................................... ixGears .............................................................. ixSeals ............................................................... xMounting Surfaces ........................................... xFasteners ........................................................ xiTapered Ball Joint Removal .............................. xi

Introduction .................................................... 1Operation .........................................................1Technical Specifi cations ...................................1Identifi cation Tag .............................................2Model Nomenclature ........................................2Front View ........................................................2

Inspection ....................................................... 3Checking Steering Knuckle Vertical End Play .....3Checking the Upper and Lower King Pin Bushings for Wear ............................................4Inspecting the Tie Rod Ends ..............................5

Lubrication & Maintenance .............................. 6King Pins on Sealed & Easy Steer Front Axles ....6Ball Studs on the Steering Arm, the Tie Rod Arm Ends, and the Drag Link .............................6Oil-Lubricated Wheel Bearings .........................6Grease-Lubricated Wheel Bearings ..................7Tightening Draw Key Nuts .................................7Checking Steering Arm Nut ...............................7Lubricant Specifi cations ...................................8

FS25 ............................................................... 9Exploded View ..................................................9

Adjustments .................................................. 11Inspection Before Alignment ......................... 11Front Wheel Alignment .................................. 11Minor Front Wheel Alignment ......................... 11Major Front Wheel Alignment ......................... 12Check & Adjust Wheel Bearings ..................... 12Adjust the Maximum Turn Angle ..................... 14Adjust Power Steering Pressure Relief (Setting the Maximum Turn Angle) ................. 15Hydraulic Pressure Relief in the Steering Gear 16Turning Radius Angle ..................................... 16King Pin Inclination ....................................... 17Camber Angle ............................................... 17Caster Angle ................................................. 18Adjusting the Toe-In Specifi cation ................. 19

Removal ........................................................ 20Removing the Wheel Ends ............................. 20Removing the Drag Link ................................. 21Removing the Steering Arm ........................... 21Removing the Tie Rod Arms, Tie Rod Ends, & the Cross Tube ........................................... 22Removing the King Pins & Steering Knuckle ... 23Removing Threaded Draw Keys ...................... 23Removing the King Pin Bushings from the Knuckle ........................................................ 24

Preparing Parts for Assembly .......................... 25Parts Inspection ............................................ 25

Installation ................................................... 27Installing Easy Steer King Pin Bushings in the Knuckle ................................................... 27Reaming the Easy Steer Bushings .................. 28Installing the Inner Knuckle Bore King Pin Seals ............................................................ 30Installing the Knuckle to Axle Beam ............... 31Installing the Tie Rod Arms ............................ 34Tie Rod Assembly .......................................... 35Installing the Steering Arm ............................ 35Installing the Drag Link .................................. 36Installing the Brake Components & Wheel Ends ................................................... 36

Torque Specifi cations .................................... 37

Troubleshooting ............................................. 38

Service Notes

iii

Service Notes

This service manual describes the service and repair procedures for the FS25 front non-drive steer axle. The information contained in this manual is current at the time of publication and is subject to change without notice or liability.

Follow all company procedures when you service or repair equipment or components. Understand all instructions before performing any product service. Some procedures require the use of special tools for safe and correct ser-vice. Failure to use special tools when required can cause serious personal injury to service personnel, as well as, damage to equipment and components.

The instructions contained in this service manual are intended for use by skilled and experienced mechanics knowledgeable in the installation, repair, and replacement of the AxleTech product described herein.

! DANGERInstallation, maintenance, and replacement of such prod-ucts requires a high degree of skill and experience. The consequences of improper installation, maintenance, or replacement (including the use of inferior or substandard components) are grave and can result in product failure and resulting loss of control of the vehicle, possible injury or death of persons, and/or possible future or additional product damage.

AxleTech does not authorize anyone, other than highly skilled and experienced individuals, to attempt to utilize the instructions contained in this manual for the installa-tion, maintenance, or replacement of the product de-scribed herein, and AxleTech shall have no liability of any kind for damages arising out of (or in connection with) any other use of the information contained in this manual.

UpdatesFor the latest version of this manual, please visit AxleTech International’s web site at www.axletech.com.

NotationsAxleTech International uses the following notation to warn the user of possible safety problems and to provide information that will prevent damage to equipment and components:

! DANGERA DANGER indicates a procedure that you must follow exactly or it will cause death or serious injury.

! WARNINGA WARNING indicates a procedure that you must follow exactly or it may cause death or serious injury.

! CAUTIONA CAUTION indicates a procedure that you must follow exactly to avoid damaging equipment or components.

NOTEA NOTE indicates an operation, procedure, or instruction that is important for proper service. A NOTE can also supply information that will help to make service quicker and easier.

Asbestos and Non-Asbestos Fibers Warning

iv


OSHA* Toxic and Hazardous Substances 29 CFR 1910.1001

Work practices and engineering controls for automotive brake and clutch inspection, disassembly, repair and assembly -- Mandatory

This mandatory appendix specifi es engineering controls and work practices that must be implemented by the employer during automotive brake and clutch inspection, disassembly, repair, and assembly operations.

Proper use of these engineering controls and work practices by trained employees will reduce employees’ asbestos exposure below the permissible exposure level during clutch and brake inspection, disassembly, repair, and assembly operations. The employer shall institute engineering controls and work practices using either the method set forth in paragraph [A] or paragraph [B] of this appendix, or any other method which the employer can demonstrate to be equivalent in terms of reducing employ-ee exposure to asbestos as defi ned and which meets the requirements described in paragraph [C] of this appendix, for those facilities in which no more than 5 pairs of brakes or 5 clutches are inspected, disassembled, reassembled and/or repaired per week, the method set forth in para-graph [D] of this appendix may be used:

[A] Negative Pressure Enclosure/HEPA Vacuum System Method

(1) The brake and clutch inspection, disassembly, repair, and assembly operations shall be enclosed to cover and contain the clutch or brake assembly and to prevent the release of asbestos fi bers into the worker’s breathing zone.

(2) The enclosure shall be sealed tightly and thoroughly in-spected for leaks before work begins on brake and clutch inspection, disassembly, repair, and assembly.

(3) The enclosure shall be such that the worker can clearly see the operation and shall provide impermeable sleeves through which the worker can handle the brake and clutch inspection, disassembly, repair and assembly. The integri-ty of the sleeves and ports shall be examined before work begins.

(4) A HEPA-fi ltered vacuum shall be employed to maintain the enclosure under negative pressure throughout the op-eration. Compressed-air may be used to remove asbestos fi bers or particles from the enclosure.

(5) The HEPA vacuum shall be used fi rst to loosen the as-bestos containing residue from the brake and clutch parts and then to evacuate the loosened asbestos containing material from the enclosure and capture the material in the vacuum fi lter.

(6) The vacuum’s fi lter, when full, shall be fi rst wetted with a fi ne mist of water, then removed and placed immedi-ately in an impermeable container, labeled according to paragraph (j)(5) of this section and disposed of according to paragraph (k) of this section.

(7) Any spills or releases of asbestos containing waste material from inside of the enclosure or vacuum hose or vacuum fi lter shall be immediately cleaned up and dis-posed of according to paragraph (k) of this section.

[B] Low Pressure/Wet Cleaning Method

(1) A catch basin shall be placed under the brake assem-bly, positioned to avoid splashes and spills.

(2) The reservoir shall contain water containing an organic solvent or wetting agent. The fl ow of liquid shall be con-trolled such that the brake assembly is gently fl ooded to prevent the asbestos-containing brake dust from becom-ing airborne.

(3) The aqueous solution shall be allowed to fl ow between the brake drum and brake support before the drum is removed.

(4) After removing the brake drum, the wheel hub and back of the brake assembly shall be thoroughly wetted to suppress dust.


v

(5) The brake support plate, brake shoes and brake com-ponents used to attach the brake shoes shall be thor-oughly washed before removing the old shoes.

(6) In systems using fi lters, the fi lters, when full, shall be fi rst wetted with a fi ne mist of water, then removed and placed immediately in an impermeable container, labeled according to paragraph (j)(4) of this section and disposed of according to paragraph (k) of this section.

(7) Any spills of asbestos-containing aqueous solution or any asbestos-containing waste material shall be cleaned up immediately and disposed of according to paragraph (k) of this section.

(8) The use of dry brushing during low pressure/wet clean-ing operations is prohibited.

[C] Equivalent Methods

An equivalent method is one which has suffi cient written detail so that it can be reproduced and has been demon-strated that the exposures resulting from the equivalent method are equal to or less than the exposures which would result from the use of the method described in paragraph [A] of CFR 1910.1001. For purposes of making this comparison, the employer shall assume that expo-sures resulting from the use of the method described in paragraph [A] of this appendix shall not exceed 0.016 f/cc, as measured by the OSHA reference method and as averaged over at least 18 personal samples.

[D] Wet Method

(1) A spray bottle, hose nozzle, or other implement capa-ble of delivering a fi ne mist of water or amended water or other delivery system capable of delivering water at low pressure, shall be used to fi rst thoroughly wet the brake and clutch parts. Brake and clutch components shall then be wiped clean with a cloth. Any wastewater generated must be captured and properly disposed of without allow-ing it to dry on any surfaces.

(2) The cloth shall be placed in an impermeable container, labeled according to paragraph (j)(4) of the standard and then properly disposed of as an asbestos waste, or the cloth shall be laundered in a way to prevent the release of asbestos fi bers in excess of 0.1 fi ber per cubic centimeter of air.

(3) Any spills of solvent or any asbestos containing waste material shall be cleaned up immediately according to paragraph (k) of this section.

(4) The use of dry brushing during the wet method opera-tions is prohibited.

[59 FR 40964, Aug. 10, 1994; 60 FR 33972, June 29, 1995; 77 FR 17778, March 26, 2012]

For more information, visit www.osha.gov, or call OSHA at 1-800-321-OSHA(6742), TTY 1-877-889-5627.

*References to OSHA, NIOSH, MSHA, and EPA, which are regulatory agencies in the United States, are made to provide further guidance to employers and workers em-ployed within the United States. Employers and workers employed outside of the United States should consult the regulations that apply to them for further guidance.

Service Precautions

vi

Service Precautions

! DANGER• ALWAYS WEAR PROPER EYE PROTECTION AND

OTHER REQUIRED PERSONAL PROTECTIVE EQUIPMENT TO PREVENT PERSONAL INJURY WHEN PERFORMING VEHICLE SERVICE.

• WORK IN A WELL-VENTILATED AREA.

• NEVER USE GASOLINE, OR SOLVENTS CONTAINING GASOLINE. GASOLINE CAN EXPLODE.

• DO NOT USE HOT SOLUTION TANKS OR WATER AND ALKALINE SOLUTIONS TO CLEAN GROUND OR POLISHED PARTS. DOING SO WILL CAUSE DAMAGE TO THE PARTS.

• USE HOT SOLUTION TANKS OR ALKALINE SOLUTIONS CORRECTLY. READ THE MANUFACTURER’S INSTRUCTIONS BEFORE USING HOT SOLUTION TANKS AND ALKALINE SOLUTIONS. THEN CAREFULLY FOLLOW THE INSTRUCTIONS.

• SOLVENT CLEANERS CAN BE FLAMMABLE, POISONOUS, AND CAUSE BURNS. EXAMPLES OF SOLVENT CLEANERS ARE CARBON TETRACHLORIDE, EMULSION-TYPE, AND PETROLEUM-BASED CLEANERS. READ THE MANUFACTURER’S INSTRUCTIONS BEFORE USING A SOLVENT CLEANER, THEN CAREFULLY FOLLOW THE INSTRUCTIONS. ALSO FOLLOW THE PROCEDURES BELOW.

• PLACE THE VEHICLE ON A LEVEL FLOOR AND CHOCK THE WHEELS TO HELP PREVENT THE VEHICLE FROM MOVING. NEVER WORK UNDER A RAISED VEHICLE SUPPORTED BY ONLY A FLOOR JACK. ALWAYS SUPPORT A RAISED VEHICLE WITH SAFETY STANDS. CHOCK THE WHEELS AND MAKE SURE THE UNIT WILL NOT ROLL BEFORE RELEASING BRAKES. A JACK CAN SLIP OR FALL OVER. SERIOUS PERSONAL INJURY CAN RESULT.

• IMPROPER JACKING AND SUPPORT METHODS CAN CAUSE STRUCTURAL DAMAGE THAT RESULTS IN LOSS OF VEHICLE CONTROL, SEVERE PERSONAL INJURY OR DEATH. REFER TO THE VEHICLE MANUFACTURER FOR PROPER JACKING AND SUPPORT METHODS.

! WARNINGFOLLOW THE SPECIFIED PROCEDURES IN THE INDICAT-ED ORDER TO AVOID PERSONAL INJURY OR EQUIPMENT MALFUNCTION/DAMAGE.

BEFORE STARTING A VEHICLE:

• Sit in the driver’s seat

• Place the shift lever in neutral

• Set the parking brake

BEFORE WORKING ON A VEHICLE OR LEAVING THE CAB WITH ENGINE RUNNING:



• Chock the wheels

WHEN PARKING THE VEHICLE OR LEAVING THE CAB:



! CAUTION• DO NOT RELEASE THE PARKING BRAKE OR

ATTEMPT TO SELECT A GEAR UNTIL THE AIR PRESSURE IS AT THE CORRECT LEVEL.

• TO AVOID DAMAGE TO THE TRANSMISSION DURING TOWING:


• Lift the drive wheels off of the ground or disconnect the driveline

• DO NOT OPERATE VEHICLE IF THE ALTERNATOR LAMP IS LIT OR IF THE GAUGES INDICATE LOW VOLTAGE.

TowingDue to the wide range of environments and applications for AxleTech axles, it is recommended to follow the towing instructions from the vehicle Original Equipment Manufac-turer (OEM).

Service Precautions

vii

Repair Warnings

! DANGERUSE OF OTHER THAN RECOMMENDED TOOLS, PARTS, AND INSTRUCTIONS LISTED IN THIS PUBLICATION MAY PLACE THE SAFETY OF THE SERVICE TECHNICIAN OR VEHICLE DRIVER IN JEOPARDY.

DO NOT WELD REPAIR, HEAT, BEND, OR RECONDITION AXLE COMPONENTS. THIS WILL REDUCE COMPONENT STRENGTH, VOID AXLETECH’S WARRANTY, AND CAN RESULT IN SERIOUS PERSONAL INJURY AND DAMAGE TO COMPONENTS. ALWAYS REPLACE DAMAGED OR OUT-OF-SPECIFICATION COMPONENTS.

• When disassembling various assemblies, lay all parts on a clean bench in the same sequence as removed to simplify assembly and reduce the possibility of losing parts.

• Provide a clean work area. Make sure no dirt or foreign material enter the unit during repair and assembly.

• Disconnect the vehicle’s battery before removing or installing electronic parts.

• The location of components varies with each OEM.

• The removal and installation procedure described for each component may vary between vehicles.

• Use a rubber mallet for disassembly and assembly procedures. NEVER hit steel parts with a steel hammer. Pieces of a part can break off and cause serious personal injury.

• Remove nicks, marks, and burrs from parts having machined or ground surfaces. Use a fi ne fi le, India stone, emery cloth or crocus cloth for this purpose.

Torque Specifi cations• Tightening torque specifi cations indicated in this

manual must be adhered to at all times.

• A tightening torque weaker than indicated may lead to a shearing stress and may break the bolt.

• A stronger tightening torque may lead to yielding of the bolt or an increasing risk of cracking.

Cleaning• Remove gasket material using a gasket scraper taking

care not to damage machined surfaces.

• Steam clean or pressure wash the assembly after plugging all breathers, vents, and hydraulic inlets.

NOTE: NEVER direct full pressure at any of the seals (input shaft, wheel hubs, or brakes).

• Use solvent cleaners or alkaline solutions to clean all metal parts with rough surfaces. Parts must remain in hot solution tanks until completely cleaned and heated. Rinse alkaline solution off with water after cleaning.

• Use solvent cleaners and a brush to clean all metal parts that have ground or polished surfaces.

NOTE: NEVER clean ground or polished surfaces with water, steam, alkaline solution, or place in a hot tank.

• Dry all parts after washing using clean rags or paper towels.

• Apply a light oil fi lm to all parts to be reused and reassembled.

• If parts are being stored after cleaning, apply a corrosion-preventive material to all machined surfaces. Store the parts in a special paper or other material that prevents corrosion.

Damaged Components• All damaged components must be replaced by new

components.

• Clean and repair the threads of fasteners and holes. Use a die or tap of the correct size or a fi ne fi le for this purpose.

• Replace any fastener if corners of the head are worn.

• Since the cost of a new part is generally a small fraction of the total cost of downtime and labor, avoid reusing a questionable part that could lead to additional repairs and expense.

• Always use genuine AxleTech replacement parts.

Service Precautions

viii

Repair Welding

! DANGERTHE HIGH TEMPERATURE CAUSED BY THE OPEN FLAME FROM A CUTTING TORCH CAN IGNITE THE OIL IN THE AXLE HOUSING AND CAN CAUSE SERIOUS PERSONAL INJURY.

In the interest of safety and preserving the service life of drive axle assemblies, AxleTech recommends that assem-blies are not repair welded. Repair welding can detract from the structural integrity of a component, particularly to heat treated parts where the benefi t of heat treatment may be nullifi ed by welding.

Since it can be extremely hazardous and detrimental to repair weld components of any kind, repair welding can be approved only where stringent controls are imposed and equipment, customarily located at manufacturing facilities, is employed, so as to minimize the potentially detrimental eff ects of repair welding.

Please contact AxleTech if you believe that repair welding will work for your particular situation.

OmissionsEvery eff ort has been made to ensure the accuracy of all information in this manual. However, AxleTech makes no expressed or implied warranty or representation based on the enclosed information. Any errors or omissions may be reported to AxleTech, 1400 Rochester Road, Troy, Michi-gan, 48083 USA.

General Assembly Instructions

ix

General Assembly Instructions Tapered Roller Bearings

! CAUTIONDRY BEARINGS WITH CLEAN PAPER OR RAGS. NEVER USE COMPRESSED AIR, WHICH CAN CAUSE ABRASIVE PARTICLES TO CONTAMINATE THE BEARINGS. DAM-AGE TO COMPONENTS AND REDUCED LINING LIFE CAN RESULT.

If parts are clean and properly lubricated, it is rare for bearings to be damaged. Proper installation is also criti-cal to avoid vibration, noise, and reduced bearing life.

Bearings should be replaced when:

• Bearing surfaces show abnormal wear

• Bearings are chipped (due to improper cleaning during assembly, improper lubrication, or a broken component inside the case)

• Centers of the large diameter end of the rollers are worn level with or below the surface

• Centers of the large diameter end of the rollers are worn to a sharp edge

• A roller groove is worn in the cup or cone inner race surfaces visible at the small or large diameter ends of both parts

• Deep cracks or breaks are present in the cup, cone inner race, or roller surfaces

• Bright wear marks are present on the outer surface of the roller cage

• Etching and pitting is present on the rollers and on surfaces of the cup and cone inner race that touches the rollers

• Spalling or fl aking is present on the cup and cone inner race surfaces that touch the rollers

During disassembly:

• Remove bearings with pullers designed for this purpose to avoid damaging the bearing.

• Carefully wash and re-lubricate all bearings as removed and protectively wrap until ready for use.

• Store all bearings in a dry and clean area to minimize the possibility of corrosion, contamination, or other damage.

During assembly:

• Install bearings in a clean environment, free from dust, debris, moisture, and other contaminants.

• Machining, fi ling, soldering, grinding, etc. should be kept away from the assembly area to prevent contaminating the bearings.

• Check the cleanliness of the bearing:• If the bearing is new, unpack it immediately

before assembly.• Used bearings should be cleaned with petrol or

benzine and then oiled.

• Verify the bore is deburred and cleaned before installing the bearing. Use 180-grit emery cloth to remove small imperfections in the metal.

• Bearings are installed the easiest by cooling or heating (in hot oil to 80°C) instead of using a press. Do not apply any shock or impact techniques (like hammering) to install the bearings.

• When a bearing has been heated for assembly, apply a small amount of grease or oil after assembly.

• When installing on a tight shaft, force is to be applied to the inner ring only.

Castings• Inspect for damage or cracking. Replace as required.

NEVER weld to repair the casting.

Gears• Inspect for pitting or damage. Replace as required.

• Replace beveled gear set, as required, with a matched set.

• Replace thrust washer, diff erential side gear, and pinion gear with a new matched set. Do not mix old and new parts. Damage to components can result.


x

Seals

! WARNINGWHEN APPLYING SOME SILICONE GASKET MATERIALS, SMALL AMOUNTS OF ACID VAPOR ARE PRESENT. TO PREVENT POSSIBLE SERIOUS INJURY, THE WORK AREA MUST BE WELL-VENTILATED. IF THE SILICONE GASKET MATERIAL GETS INTO YOUR EYES, FLUSH THEM WITH WATER FOR 15 MINUTES. HAVE YOUR EYES CHECKED BY A DOCTOR AS SOON AS POSSIBLE.

Recommended Lubricant: Gear Oil

• O-rings: After removal, always replace with new ones.

• Lipped seals: All disassembled seals shall be discarded and replaced by a new seal.

• Gaskets: After disassembly, always install a new paper or silicone gasket.

• Silicone Gaskets - Apply a 0.125” (3.18 mm) diameter continuous bead of silicone gasket material around one surface. Also apply the gasket material around the edge of all the fastener holes on that surface. Assemble immediately and wait 20 minutes before fi lling the assembly with lubricant.

0.125" (3.18 MM)DIAMETERSILICONE GASKETMATERIAL BEAD

! CAUTIONTOO MUCH GASKET MATERIAL CAN BLOCK LUBRI-CATION PASSAGES. DAMAGE TO COMPONENTS CAN RESULT.

During assembly:

• Verify the seal bearing surface edges are free of burrs and nicks that may damage seals.

• Lubricate properly:• Lubricate the entire interior surface of the ring

and primarily the seal lips.• Pack the space between the lips with grease.

NOTE: Do not use an excessive quantity of lubricant since liquefaction may occur during operation and appear outside the housing. This could easily be mistaken for a leak.

• The ring shall be engaged in its housing perpendicularly and concentrically to the shaft.

• Do not damage the seal lips and turn them over during installation.

Mounting SurfacesFor all mounting surfaces that do not use an o-ring seal, use Loctite 5699 RTV Silicone Gasket.

Product characteristics:

• Color: Grey

• Adhesive power: Weak, nevertheless, do not use on centering; only on the faces.

• Temperature Resistance: -67 to 392°F (-55 to 200°C)

• TO BE USED WITH CARE: Avoid any contact with eyes and skin.

During disassembly:

• In the event of sticking, tap the parts to break the Loctite fi lm.

• Remove particles of Loctite as thoroughly as possible.

• Clean and carefully degrease surfaces (any lubricant prevents setup therefore making the product ineff ective) using a solvent or by washing the parts.

• Let all components dry completely.

During assembly:

• Apply a single bead to one of the mating surfaces well around the attachment holes.

• Assemble the parts and tighten to the required torque.

• Leave to dry: Parts can be handled after 30 minutes.

• Total setup time: 18 to 24 hours


xi

FastenersWhen installing fasteners without pre-applied adhesive, Loctite 243 Blue Threadlocker must be used unless other-wise stated.

NOTE: Do not apply adhesives or sealants to fasteners with pre-applied adhesive, or to fastener holes.

Product characteristics:

• Color: Pale blue

• Temperature Resistance: -67 to 302°F (- 55 to 150°C)

• TO BE USED WITH CARE: Avoid any contact with eyes and skin.

During disassembly:

• If the removal of a capscrew becomes diffi cult due to a worn head or unusually high breakaway torque, the locking strength can be reduced by heating the threaded area to approximately 300°F (150°C). Heat slowly to avoid thermal stresses on the diff erential case and gears.

• Clean excess material off all surfaces as thoroughly as possible.

• Clean and carefully degrease surfaces (any lubricant prevents setup therefore making the product ineff ective) using a solvent or by washing the parts.

• Let all components dry completely.

• Replace any fastener if corners of the head are worn.

• Replace washers if damaged.

• Clean and repair threads of fasteners and holes. Use a die or tap of the correct size or a fi ne fi le for this purpose.

! CAUTIONTHREADS MUST BE WITHOUT DAMAGE AND CLEAN SO THAT ACCURATE ADJUSTMENT AND CORRECT TORQUE VALUES CAN BE APPLIED TO FASTENERS AND PARTS.

During assembly:

• Apply one drop to the threads, preferably at the end of the screw, of Loctite 243 Blue Threadlocker.

• Assemble the parts and tighten to the required torque.

• All screws shall be tightened within 5 minutes following assembly of the parts. The unit can be used 10 minutes after assembling.

NOTE: To reduce setup time, spray Loctite 7649 Locquic Primer N activator on the threads, allow to evaporate, and then apply Loctite 243.

Tapered Ball Joint RemovalCarriage ball joints use a tapered attachment fi t to their mating component. Often, it is not practical to procure a special tool to split the taper and separate the com-ponents. AxleTech Service recommends that ball joint tapered joints housed within steel or ductile iron com-ponents can be split using a “shock method”. The shock method involves impacting the component, with a steel hammer, close to the tapered location. (DO NOT directly impact the ball joint or stud directly.) This action tends to “shock” the tapered joint loose and is a common practice by AxleTech Service.

Introduction

1

IntroductionOperationThe AxleTech FS25 Non-Drive Steer Axle is engineered to meet the increasing demands of the various On/Off -Road market vocations. With a nominal rated capacity of 25,600 lbs. (11,600 kg.), the FS25 covers a broad vehicle range including: truck mounted hydraulic cranes, agricultural, construction, and specialty chassis applications.

Engineered for a variety of specialty vehicle applications, the FS25 features 16.5” x 6” and 7” Q Plus™ (419x152 and 178mm) heavy-duty cam brakes and tubular steel beam construction for multiple OEM vehicle mounting confi gurations. With a standard spindle to beam centerline drop of 1.5” (38.1mm), the suspension height may be varied. Multiple track widths are achieved by varying the beam lengths.

The 6.375” (162mm) O.D. tubular steel beam will accommodate a variety of bracket confi gurations. The 1.5” (38mm) drop and multiple bracket confi gurations make the FS25 the most versatile heavy-duty steer axle in the specialty vehicle industry. The straight tie rod design optimizes tie rod strength, and also enhances protection behind the tubular beam from external damage. The FS25 axle is available for either a single or tandem vehicle installation; also has options on dual steer arms, and tie rod arms available to improve nominal Ackerman steer. The FS25 axle has both inch/metric conventional wheel studs as available mountings to improve OEM vehicle installation fl exibility.

When replacing parts, only use factory original parts and parts sets. Parts must be ordered from AxleTech. Any damage to parts not described in this manual must be repaired or replaced using original parts.

Technical Specifi cationsCapacity 25,600 lb / 11,600 kg

Housing Fabricated tubular steel beam

Flange to fl ange 92.57 in / 2,351 mm, 95.61 in / 2,428 mm, or 103.27 in / 2,623 mm

Wheel mounting Stud piloted, 10 stud, 11.3 in / 286 mm or hub piloted, 10 stud, 13.2 / 335 mm bolt circle

Steering arms Dual

Mounting brackets As requested

Brakes 16.5 in x 6.00 in (419 mm x 152 mm) s-cam with automatic slack adjusters

Brake chambers Type 30

ABS Optional tone ring, sensors, and connectors

Typical axle weight 1,295 lb / 587 kg for 95.61 in / 2,428 mm fl ange to fl ange

Typical oil capacity 1 pt / 0.57 L per wheel end

Introduction

2

Identifi cation TagAll products are identifi ed by the model and serial number. This information is stamped on the identifi cation tag and affi xed to the case. Have reference numbers handy when ordering replacement parts or requesting service repairs.

MODEL FS25150ANLXICUST NO 700028SERIAL NO 601018 OSRATIO DATE 02-03

DO NOT REMOVE OR DESTROY THE IDENTIFICATION TAGS.

Model NomenclatureF S - XX - 1 5 0 X - N LX X

TypeS - Non-Drive Steer

GAWR Pounds

Axle FamilyF - Front

Exact Specification

KPI0 - 79.6” (2,022mm)5 - 72.0” (1,829mm)7 - 68.9” (1,750mm)

Beam, Kingpin, Bushing1 - Straight Kingpin w/Easy Steer Bushing

Spindle to Beam Centerline Drop0 - 1.50” (38mm)

Major Design VariationA - Conventional Knuckle

BrakesLX - Q Plus™ Cam

Manufacturing LocationN - North America

Front View

STEERING ARM

KNUCKLE

TIE ROD ENDTIE ROD CROSS TUBE ASSEMBLY

TIE ROD ARM

Inspection

3

Inspection

! WARNINGTO PREVENT SERIOUS EYE INJURY, ALWAYS WEAR EYE PROTECTION WHEN PERFORMING VEHICLE MAINTE-NANCE OR SERVICE.

! DANGERTHE REPAIR OR RECONDITIONING OF FRONT AXLE COMPONENTS IS NOT ALLOWED. AXLETECH RECOM-MENDS REPLACING DAMAGED OR OUT-OF-SPECIFICA-TION COMPONENTS. THE TUBULAR AXLE BEAM CAN ONLY BE WELDED AS DEFINED BY WRITTEN AGREE-MENT WITH AXLETECH’S ENGINEERING DEPARTMENT. ALL OTHER MAJOR COMPONENTS ARE HEAT TREATED AND TEMPERED. THOSE COMPONENTS CANNOT BE BENT, WELDED, HEATED, OR REPAIRED IN ANY WAY WITHOUT REDUCING THE STRENGTH OR LIFE OF THE COMPONENT, THUS VOIDING THE WARRANTY AND MAY CAUSE A VEHICLE ACCIDENT WHICH CAN RESULT IN SERIOUS PERSONAL INJURY.

Perform the following during an inspection.

• Fasteners - Ensure all fasteners are tightened to the specifi ed torque. Use a torque wrench to check the torque in a tightening direction. As soon as the fastener starts to move, record the torque. Correct if necessary. Replace any worn or damaged fasteners.

• Wear and Damage - Inspect the parts of the axle for wear and damage. Look for bent or cracked parts. Replace all worn or damaged parts.

• Pivot Points - Make sure looseness does not exist at the pivot points. Make sure the pivot points are lubricated.

• Operation - Ensure all the parts move freely through the complete turning radius.

• Tire Wear - Inspect the tires for wear patterns indicating suspension damage or misalignment.

Checking Steering Knuckle Vertical End Play1. Place blocks in front and behind the rear wheels to

prevent the vehicle from moving.

! DANGERPARK THE VEHICLE ON A LEVEL SURFACE. BLOCK THE WHEELS TO PREVENT THE VEHICLE FROM MOVING. SUPPORT THE VEHICLE WITH SAFETY STANDS. NEVER WORK UNDER A VEHICLE SUPPORTED ONLY BY JACKS. JACKS CAN SLIP AND FALL OVER. SERIOUS PERSONAL INJURY CAN RESULT.

2. Use a jack to raise the vehicle until the front wheels are off the ground. Support the front axle with safety stands.

3. Install a dial indicator so the base is on the I-beam and the tip is on the top knuckle cap.

4. Place a pry bar between the boss for the tie rod arm and the I-beam. Push the knuckle to the bottom of vertical travel.NOTE: If one bushing requires replacement, then replace both bushings in the knuckle.

Pry Bar

Inspection

4

5. Set the dial indicator to zero (0).

6. Use the pry bar to push the knuckle upward. Record the reading on the dial indicator.

The reading must be 0.001-0.025” (0.025-0.635 mm) for new or rebuilt axles and 0.001-0.065” (0.025-1.650 mm) for axles in service.

Pry Bar

If the reading is outside of specifi cation, remove the knuckle and add shims to the shim pack. See "Removing the King Pins & Steering Knuckle" on page 23.

Checking the Upper and Lower King Pin Bushings for Wear1. Place blocks in front of and behind the rear wheels to

prevent the vehicle from moving.


2. Use a jack to raise the vehicle until the wheels are off the ground. Support the vehicle with safety stands.

3. Check the upper king pin bushing for wear. Install a dial indicator so the base is on the I-beam and the tip is against the side of the top of the knuckle.

NOTE: If one bushing requires replacement, then replace both bushings in the knuckle.

4. Set the dial indicator on zero (0).

Inspection

5

5. Move the top of the tire side-to-side towards and away from the vehicle. If the dial indicator moves a total of 0.010” (0.254 mm), the upper bushing is worn or damaged. Replace both bushings. See "Removing the King Pin Bushings from the Knuckle" on page 24.

6. Check the lower king pin bushing. Install a dial indicator so the base is on the I-beam and the tip is against the side of the bottom of the knuckle.

7. Set the dial indicator on zero (0).

8. Move the bottom of the tire side-to-side towards and away from the vehicle. If the dial indicator moves a total of 0.010” (0.254 mm), the lower bushing is worn or damaged. Replace both bushings. See "Removing the King Pin Bushings from the Knuckle" on page 24.

Inspecting the Tie Rod Ends1. Park the vehicle with the steering wheels in the

straight-ahead position.

TieRodEnd

Tie Rod ArmCrossTube

2. Place blocks in front of and behind the rear wheels to prevent the vehicle from moving. Set the parking brake.

3. Remove dirt and grease from the tie rod end seals.

4. Place the indicator base on the bottom of the tie rod arm.

5. Place the indicator tip near the ball stud center (grease fi tting) of the tie rod end.

6. Set the dial indicator to zero (0).

Tie Rod End

! CAUTIONCHECK THE TIE ROD END PLAY BY HAND. NEVER USE A PRY BAR. IF A PRY BAR IS USED, READINGS FROM THE DIAL INDICATOR WILL NOT BE ACCURATE.

7. Move the tie rod and cross tube assembly up and down by hand.

8. Record the dial indicator reading. If the dial indicates a reading of more than 0.060” (1.52 mm), tie rod end replacement is required.

9. Place the dial indicator on the tie rod end assembly at the opposite side of vehicle and repeat Steps 1 to 8.

Lubrication & Maintenance

6



Lubricate the king pins, the ball studs on the tie rod arm ends, the ball stud on the steering arm, and grease-lu-bricated wheel bearings with the approved lubricant. See Table A on page 8.

Lubricate the oil-lubricated wheel bearings with the oil specifi ed in Table B on page 8.

King Pins on Sealed & Easy Steer Front Axles


On sealed and Easy Steer front axles, the grease fi ttings are on the top and bottom king pin caps of the knuckle.

1. Ensure the tires touch the ground. DO NOT RAISE THE VEHICLE.

2. Clean all grease fi ttings prior to lubrication.

3. Lubricate the king pins through the grease fi ttings on the top and bottom of the knuckle.

GREASEFITTING

Lube mustcome fromhere

4. Apply lubricant until new lubricant comes from the thrust bearing seal and the upper shim pack.

Ball Studs on the Steering Arm, the Tie Rod Arm Ends, and the Drag Link1. Ensure the tires touch the ground.

DO NOT RAISE THE VEHICLE.

2. Apply lubricant until new lubricant comes from the boot.

GREASEFITTING

Lube mustcome fromhere

Oil-Lubricated Wheel Bearings1. Check the level on the cap.

2. If the oil level is not at the specifi ed level on the cap:

• Remove the oil fi ll plug

• Add the recommended oil until it is at the specifi ed level

OIL LEVEL


7

Grease-Lubricated Wheel Bearings1. Raise the front of the vehicle until the front wheels are

off the ground.

2. Support the vehicle with safety stands.

3. Remove the tire and wheel assembly.

4. Remove and disassemble the hub. See "Removing the Wheel Ends" on page 20.

5. Remove the old lubricant from all parts.

6. Discard the seals.

7. Inspect the wheel bearings for damaged or wear. See "Tapered Roller Bearings" on page ix.

8. Force the specifi ed lubricant from the large end of the cones into the cavities between the rollers and cage.

9. Pack the hub between the bearing cups with lubricant to the level of the smallest diameter of the cups.

LUBE

10. Install the inner and outer bearing cones into the cups in the hubs. The bearing cups must be pressed tight against the shoulder in the hubs.

11. Install new wheel seals in the hubs.

12. Install the hub and the wheel and tire assembly.

13. Install the outer wheel bearing cone in the hub.

14. Install the adjusting nut.

15. Adjust the wheel bearings. See "Check & Adjust Wheel Bearings" on page 12.

Tightening Draw Key NutsNOTE: This procedure applies to all AxleTech front non-drive steer axles in off -highway use.

Tighten the nuts holding the draw keys on the side of the knuckle to 30-45 lbs. ft. (41-61 N·m) at the following intervals:

• After the fi rst 250 hours of new vehicle operation

• Every 6,000 hours of operation or once a year

Draw Key Nut30-45 lbs ft(41-61 N m)

Checking Steering Arm NutCheck the steering arm nut for minimum 775 lbs. ft. (1054 N·m) torque. If steering arm nut torque has fall-en below minimum torque, tighten to 775-1450 lbs. ft. (1054-1970 N·m) torque. Check steering arm nut torque every 12,000 hours or 24 months.


8

Lubricant Specifi cations Table A

Component Greasing Interval Grease AxleTech

Specifi cationNLGI

Grade Grease Type Outside Temperature

King Pins & Bushings, Thrust Bearings, Ball Studs on Steering Arm, Tie Rod Ends and Drag Link*

6,000 hours or once a year, whichever comes fi rst

Multi-Purpose Grease**

O-617-A or O-617-B

1 or 2 Lithium12- Hydroxystearate or Lithium Complex

Refer to the grease manufacturer’s specifi cations for the temperature service limits

* Inspect the ball studs every two years for wear and damage. Service as necessary.

** Synthetic grease is often used for vehicle maintenance, however, some seals are known to expand when in contact with synthetic grease. Contact AxleTech before using any synthetic grease when performing axle service and maintenance.

Table B: Wheel End Oil Change Intervals and Specifi cations

On-Highway Operation Intervals

Off -Highway Operation Intervals

AxleTech Specifi cation

Military Specifi cation

Oil Description

Outside TemperatureF° C°

Check Oil

Level

Petroleum Oil Change

Check Oil Level

Petroleum Oil Change Min Max Min Max

1,000 miles / 1,600 km

Whichever comes fi rst: •Seals replaced •Brakes relined •100,000 miles / 60,000 km•Once a year

50 hours Whichever comes fi rst: •Seals replaced •Brakes relined•Once a year

O-76A, Gear Oil

MIL-L-2105-E

GL-5, SAE 85W/140

10 None 12 None

O-76D,Gear Oil

GL-5, SAE 80W/90

-15 None -26 None

O-76E,Gear Oil

GL-5, SAE 75W/90

-40 None -40 None

O-76J,Gear Oil

GL-5, SAE 75W

-40 36 -40 2

Heavy DutyEngine Oil

MIL-L-2104-B, -C, -D, or -E

API -CD, -CE -SF or -SG SAE 40 or 50*

10 None 12 None

Heavy DutyEngine Oil

API -CD, -CE, -SF OR -SG SAE 30**

-15 None -26 None

*Current designations are acceptable. Multi-weight engine oils are acceptable if the SAE rating ends in a 40 or 50.

** Current designations are acceptable. Multi-weight engine oils are acceptable if the SAE rating ends in a 30.

FS25

9

FS25Exploded View

12

4

3

5

6

7

89

1011

12

1514

13

16

17 18

19

2021

23

22

25

26

1327

24

6 7

8

28

31

4445

29

30

43

3233

3436 35

3837

39 4140

42

10

9

FS25

10

Item Description

1 Cotter Pin

2 Castle Nut - Drag Link to Steering Arm

3 Key

4 Steering Arm

5 Ball Stud

6 Bolt

7 Grease Fitting

8 Knuckle Cap - Greaseable

9 Gasket

10 King Pin Bushing - Easy Steer

11 Cotter Pin

12 Threaded Draw Key

13 Nut, Threaded Draw Key

14 Shims

15 Axle Beam

16 Cover-Type Bearing Seal

17 Thrust Bearing

18 Cross Tube

19 Clamp, Cross Tube

20 Lock Nut, Clamp

21 Cotter Pin

22 Castle Nut - Tie Rod Arm to Tie Rod End

23 Knukcle Tie Rod Arm

Item Description

24 Woodruff Key

25 Tie Rod End

26 Bolt, Clamp

27 3/4” Stop Bolt & Jam Nut

28 Castle Nut (Flared Base) - Steering Arm to Knuckle

29 Seal - King Pin Bushing

30 King Pin

31 Knuckle

32 Hub Grease Seal

33 Inner Wheel Bearing Cone

34 Stud

35 Hub

36 Outer Wheel Bearing Cup

37 Adjusting Nut

38 Lock Washer

39 Hubcap, Gasket, Capscrew, & Washer

40 Wheel Bearing Nut

41 Pierced Lock Ring

42 Outer Wheel Bearing Cone

43 Inner Wheel Bearing Cup

44 Castle Nut - Tie Rod Arm to Knuckle

45 Cotter Pin

Adjustments

11

Adjustments Inspection Before AlignmentCheck the following before doing a front wheel alignment.

• Inspection - See "Inspection" on page 3.

• Wheels and Tires - Check the following items:

• Ensure the tires are infl ated to the specifi ed pressure.

• Ensure the front tires are the same size and type.

• Ensure the lug nuts are tightened to the specifi ed torque.

• Ensure the wheels are balanced.

• Check for bent or damaged wheels.

• Front Suspension - Check the following items:

• Ensure all fasteners are tightened to the specifi ed torque.

• Inspect the leaf springs for wear and damage.

• Inspect the shock absorbers for wear and damage.

• Rear Axle and Rear Suspension - Front tire wear can be caused by the rear axle. If the outer edge of one front tire is worn and the inner edge of the other front tire is worn, check the following:

• Ensure all fasteners are tightened to the specifi ed torque.

• Ensure the leaf springs are not worn or damaged.

• Ensure the bushings in the leaf springs are not worn or damaged.

• Ensure the torque rods (if used) are correctly adjusted.

• Ensure the frame is not bent.

• Ensure the rear axle (especially a tandem axle) is correctly aligned. Refer to the vehicle or suspension manufacturer procedure.

• Refer to any additional rear axle and suspension recommendations and specifi cations from the vehicle manufacturer.

Front Wheel AlignmentCheck the front wheel alignment when the following occur:

• Every 12,000 hours or 24 months (normal maintenance)

• When the vehicle does not steer correctly

• To correct a tire wear condition

There are two types of front wheel alignment:

• Minor alignment

• Major alignment

Minor Front Wheel AlignmentPerform a minor front wheel alignment for all normal main-tenance conditions.

Perform the minor front wheel alignment in the following sequence:

1. Inspect all systems aff ecting wheel alignment. See "Inspection Before Alignment" on page 11.

2. Check and adjust the wheel bearings. See "Check & Adjust Wheel Bearings" on page 12.

3. Check and adjust the toe-in. See "Adjusting the Toe-In Specifi cation" on page 19.

Adjustments

12

Major Front Wheel AlignmentPerform a major front wheel alignment to correct steering and tire wear conditions in the following sequence:

1. Inspect all systems aff ecting wheel alignment. See "Inspection Before Alignment" on page 11.

2. Check and adjust the wheel bearings. See "Check & Adjust Wheel Bearings" on page 12.

3. Check and adjust the maximum turn angle. See "Adjust the Maximum Turn Angle" on page 14.

4. If the vehicle has power steering, check and adjust the pressure relief in the power steering system. See "Adjust Power Steering Pressure Relief (Setting the Maximum Turn Angle)" on page 15.

5. Check and adjust the turning radius angle (toe-out on turns or Ackerman angle). See "Turning Radius Angle" on page 16.

6. Check the king pin (or steering axis) inclination. See "King Pin Inclination" on page 17.

7. Check the camber angle. See "Camber Angle" on page 17.

! DANGERAXLE CAMBER IS NOT ADJUSTABLE. NEVER CHANGE THE AXLE CAMBER ANGLE OR BEND THE AXLE BEAM. BENDING THE AXLE BEAM TO CHANGE THE CAMBER ANGLE CAN DAMAGE THE AXLE AND REDUCE AXLE STRENGTH, AND WILL VOID AXLETECH’S WARRANTY. A BENT AXLE BEAM CAN ALSO CAUSE A VEHICLE ACCI-DENT AND SERIOUS PERSONAL INJURY.

8. Check and adjust the caster angle. See "Caster Angle" on page 18.


Check & Adjust Wheel Bearings


1. Raise the vehicle so the wheels are off the ground. Support the vehicle with safety stands.

2. Remove the capscrews, gasket, and cap from the hub.

3. Ensure the brake drum and the hub fasteners are tightened to the manufacturer’s specifi cations.

4. Attach a dial indicator with the magnetic base at the bottom of the hub or the brake drum. Adjust the dial indicator so the pointer is against the center of the knuckle. Set the dial indicator to zero (0).

NOTE: Do not push/pull at the top and the bottom of the hub or drum as this will not result in a true end play reading.

With indicator mounted at bottom, push/pull at sides of tire.

5. Measure the end play by pushing/pulling on each side of the hub or drum while looking at the dial indicator. The end play is the total travel observed. End play should be from 0.001-0.005" (0.025-0.127 mm).

6. If necessary, adjust the wheel bearings. Refer to Steps 7 to 12.

Adjustments

13

7. Wheel bearings are adjusted with double nut and lock fasteners. Bend the lock washer from the wheel bearing nut. Remove the wheel bearing nut, the lock washer, and the pierced lock ring.

NOTE: When removing or installing the adjusting nuts, use the correct socket wrench to avoid damaging the adjusting nuts.

CAP

OUTER WHEELBEARING NUT

PIERCEDLOCK RING

ADJUSTINGNUT

WHEEL BEARINGNUT LOCK WASHER(BEND ONTO OUTER

WHEEL BEARING NUT)

CAPSCREW

DOUBLE NUT AND LOCK ADJUSTMENT

8. Use a torque wrench to tighten the adjusting nut to 100 lbs. ft. (136 N·m) while rotating the tire in both directions.

! CAUTIONDO NOT STRIKE THE ADJUSTING NUT WITH A METAL HAMMER. DO NOT USE A HAMMER AND CHISEL OR DRIFT OR LOOSEN THE ADJUSTING NUT. THIS WILL DAMAGE THE NUT.

9. Loosen the nut completely and then tighten the nut to 20 lbs. ft. (27 N·m) while rotating the tire.

1. Tighten nut to 100 lbs ft (136 N m)2. Loosen nut completely3. Tighten nut to 20 lbs ft (27 N m)

10. Axles have double nut and lock fasteners:

a. Back off the adjusting nut 1/3 turn.

Double Nut and Lock Fasteners: Back off nut 1/3 turn

b. Install the pierced lock ring, the lock washer, and the wheel bearing nut.

c. Tighten the wheel bearing nuts.

d. Measure the end play. The end play must be 0.001-0.005” (0.025-0.127 mm). Refer to Steps 4-5. Readjust if necessary.

e. If end play is to specifi cation, bend washer to at least one fl at edge of outer wheel bearing nut.

11. Install the gasket and cap on the hub. Install the capscrews and tighten to 20-30 lbs. ft. (27-41 N·m).

12. Lower the vehicle to the ground. Check for correct vehicle operation.

Adjustments

14

Adjust the Maximum Turn AngleThe stop bolt on the back of the knuckle controls the max-imum turn angle.

! CAUTIONNEVER EXCEED THE MAXIMUM TURN ANGLE SPECI-FIED BY THE VEHICLE MANUFACTURER. IF THE ANGLE IS EXCEEDED, THE STEERING ARMS, THE CROSS TUBE, AND THE TIE ROD ENDS WILL BE DAMAGED.

1. Check the angle if the front tires rub against the frame or if the steering gear has been serviced.

2. Use an alignment machine to check the angle.

3. Refer to the alignment equipment manufacturer procedure.

For power steering systems, the stop bolt should NOT touch the beam. The stop bolt should always have a min-imum clearance of 1/8” (3 mm), as shown below, when the knuckle is in the full turn position.

STOP BOLT

1/8” SPACER

1/8” CLEARANCEBETWEEN STOPBOLT AND BOSS

JAM NUT

MAXIMUMTURN ANGLE

REFERENCES TO KNUCKLE FOR STOP BOLT ADJUSTMENT

For manual steering systems, AxleTech recommends a stop bolt clearance of 1/8” (3 mm). Stop bolt contact is acceptable if no other stops are used for the maximum turn angle of the steering knuckle.

! CAUTIONIF THE STOP BOLT IS MISSING, BENT OR BROKEN, THE SYSTEM REQUIRES ADJUSTMENT. SEE "MECHANICAL STOP" ON PAGE 15.

NOTE: If the steering system is out of adjustment, inspect the steering arm for damage. Use a magnetic particle or liquid dye penetrant inspection procedure to inspect the steering arm. Pay particular attention to the bend, the taper, and the area near the ball stud. Refer to the vehicle manufacturer manual for additional inspection proce-dures.

! CAUTIONIN POWER STEERING SYSTEMS, THE HYDRAULIC PRESSURE SHOULD RELEASE OR “DROP OFF” AT THE END OF THE STEERING STROKE (WITH 1/8" OR 3 MM MINIMUM CLEARANCE AT THE STOP BOLT). IF THE PRESSURE DOES NOT RELEASE, THE COMPONENTS OF THE FRONT AXLE WILL BE DAMAGED.

Adjustments

15

Two-Piece Steering 3/4" Stop Bolt1. Put a 1/8" (3 mm) spacer between the stop bolt and

the boss on the axle beam.

2. Turn the steering wheel until the boss on the axle beam touches the spacer in front of the stop bolt. Measure the turn angle.

MAXIMUMTURN ANGLE

AXLE BEAMBOSS

TWO-PIECE 3/4” STEERING STOP BOLT

1/8”SPACER

3/4” STOPBOLT

JAMNUT

2-PIECESTOP BOLTASSEMBLY

3. If the maximum turn angle does not meet vehicle manufacturer’s specifi cations, correct the maximum angle. In a power steering system, adjust the pressure relief. In a manual steering system, follow the vehicle manufacturer specifi cations.

4. When the maximum turn angle is correct:

a. Loosen stop bolt jam nut.

b. Insert 1/8" spacer and adjust the stop bolt.

c. Tighten jam nut to 65-85 lbs. ft. (68-101 N·m).

Adjust Power Steering Pressure Relief (Setting the Maximum Turn Angle)The pressure relief in the power steering system stops or reduces forces applied to the axle when the wheel is moved in the full turn position.

Check the pressure relief if the steering arm is damaged or the power steering gear is serviced.

Two types of systems are used to adjust the pressure relief.

a. Mechanical stop on the pitman arm or in the assist cylinder

b. Hydraulic pressure relief in the power steering gear

! CAUTIONAXLETECH DOES NOT RECOMMEND A POWER STEER-ING SYSTEM WITHOUT MECHANICAL STOPS OR PRES-SURE RELIEF BEFORE THE MAXIMUM TURN ANGLE IS OBTAINED. THE STOPS OR THE PRESSURE RELIEF ARE USED TO PREVENT DAMAGE TO THE AXLE.

Mechanical StopUse the mechanical stop in the steering system to adjust the pressure relief. NEVER use the stop bolt on the knuck-le alone to adjust the poppet valve pressure relief.

NOTE: Refer to the vehicle manufacturer procedures.

! CAUTIONUSE A PRESSURE GAUGE TO MAKE SURE THE PRES-SURE DROPS FROM THE MAXIMUM SYSTEM DELIVERY PRESSURE TO A MAXIMUM OF 700-1000 PSI (4825-6890 KPA) BEFORE THE FULL TURNING ANGLE IS ACHIEVED.

Steering systems with mechanical stops are adjusted when the wheels are turned to the full right and full left turn positions. The stop travel is set at 1/8" (3 mm) be-fore the stop bolt contacts the axle beam boss.

Adjustments

16

STOP BOLT

1/8” SPACER


JAM NUT

MAXIMUMTURN ANGLE

KNUCKLE POSITION AFTER PITMAN ARM /CYLINDER STOPS RESET

Hydraulic Pressure Relief in the Steering GearNOTES:

• Refer to the vehicle manufacturer procedure.

• The stop bolt should always have a minimum clearance of 1/8" (3 mm) between the stop bolt and the axle beam boss.

Hydraulic steering gears with poppet valves are adjusted with a spacer between the stop bolt in the knuckle and the boss on the axle beam. The poppet valves are ad-justed to stop or reduce steering forces from the 1/8" (3 mm) specifi ed distance between the beam boss and the spacer.

STOP BOLT

1/8” SPACER


AXLE BEAMBOSS

KNUCKLE POSITION FOR POPPET VALVE SETTING

Turning Radius AngleWhen turning, the inner wheel must turn at a greater angle than the outer wheel. This angle is the turning radius angle (often called the Ackerman angle).

CENTER LINE OFFRONT AXLE

CENTER LINEOF CHASSISCENTER LINE OF

REAR AXLE

TURNING RADIUS OR ACKERMAN ANGLE

The angle is built into the design of the tie rod arms, the tie rod ends, and the cross tube assembly to give the best possible road contact and to minimize tire wear during turns.

Check the turning radius angle with the radius plates on the alignment equipment. To determine correct turning radius angle specifi cation, refer to the vehicle manufactur-er manual.

If the angle is not within specifi cations, premature tire wear will occur. Inspect the knuckle, tie rod arms, tie rod ends, and cross tube for wear or damage. Service as necessary.

Adjustments

17

King Pin InclinationNOTE: Refer to the vehicle manufacturer for the king pin inclination specifi cations.

King pin (or steering axis) inclination is the angle mea-sured between the center line of the king pin and the vertical position (as viewed from the front of the vehicle).

CAMBERANGLE

KING PININCLINATION

KING PIN INCLINATION ANGLE

The king pin inclination and the camber angle are de-signed into the axle to place the tire tread center line in contact with the road. This reduces steering eff ort and improves directional stability.

Use an alignment machine to check the king pin inclina-tion angle. Refer to the vehicle manufacturer manual for proper inclination angle specifi cations.

The king pin inclination is not adjustable. If the inclination is not at the specifi ed angle, check the axle beam and knuckle for damage. Service as necessary.

Camber Angle

! DANGERAXLE CAMBER IS NOT ADJUSTABLE. NEVER CHANGE THE AXLE CAMBER ANGLE OR BEND THE AXLE BEAM. BENDING THE AXLE BEAM TO CHANGE THE CAMBER ANGLE CAN DAMAGE THE AXLE AND REDUCE AXLE STRENGTH, AND WILL VOID THE WARRANTY. A BENT AXLE BEAM CAN ALSO CAUSE A VEHICLE ACCIDENT AND SERIOUS PERSONAL INJURY.

Camber is the angle of the tire with respect to the ground. Camber is positive when the distance between the top of the wheels is greater than the distance at the ground.

LOAD

POSITIVE

ZERO OR NEUTRAL

CAMBER

Adjustments

18

A small amount of positive camber is built into the knuckle because camber changes with load. This results in a zero camber angle when the vehicle is operated at the normal load.

If camber is out of specifi cation by more than 1° - 1/2°, rapid or uneven tire wear will occur. Bias ply tires will show excess camber easily, while vehicles equipped with radial tires will not be as evident.

The camber angle is not adjustable. The camber angle is machined into both the axle beam and the knuckle. If the camber angle is not at the specifi ed angle, check the axle beam and the steering knuckle for damage. Service as necessary.

Table C: Camber Angle Recommendations

Conditions Camber Specifi cationLeft & Right Sides

Camber angles machined into axles: • Hubs not installed • Axle not installed in vehicle • Load not applied on axle

+1/4° Nominal

Camber angles of axles equipped with hubs: • Axle not installed in vehicle • Load not applied on axle

+1/4° (± 7/16° ) or +11/16° to –3/16° (fi nal reading)

Camber angles under load: • Axle installed in vehicle

+3/16° to –11/16° (fi nal reading)

Use an alignment machine to check the camber angle. Re-fer to the alignment equipment manufacturer procedure. Refer to the vehicle manfacturer manual to determine the correct camber setting specifi cations.

Table C above gives the specifi cation AxleTech builds into the axle, but always use the specifi cation from the vehicle manufacturer.

Caster AngleCaster is the forward or rearward tilt of the king pin center line when viewed from the side of the vehicle. The caster angle is the angle from the vertical position to the center line of the king pin. If the top of the king pin axis is toward the rear of the vehicle, the caster is positive. A slight pos-itive caster creates a self-aligning action helping to stabi-lize the vehicle after turns and for driving straight ahead.

FORWARD

NEGATIVECASTER

POSITIVECASTER

CASTER

If caster is too much, steering eff ort will increase or may amplify a shimmy condition.

The caster angle is controlled by tapered shims installed under the leaf springs. Adjust caster according to the specifi cations and procedures of the vehicle manufactur-er.

Always use an alignment machine to check the caster angle. When checking caster, refer to the alignment equip-ment manufacturer procedures.

Caster specifi cations are set by the vehicle manufacturer. Refer to the vehicle manufacturer specifi cations for the caster setting. If caster specifi cations are not available from the vehicle manufacturer, AxleTech recommends a caster setting of +1° to +2-1/2° for vehicles with man-ual steering and +2° to +4-1/2° for vehicles with power steering.

Adjustments

19

Adjusting the Toe-In Specifi cation• Unloaded Vehicles:

1/16" (1.587 mm) ± 1/32" (0.794 mm)

• Loaded Vehicles: 1/32" (0.794 mm) ± 1/32" (0.794 mm)

Toe is the relationship of the distance between the front of the front tires and the rear of the front tires.

When the front distance is less than the rear distance, the wheels are “toed in.” Toe-in is designed into the vehicle to counteract the tendency of the tires to toe-out when the vehicle is driven.

Incorrect toe-in will result in rapid tire wear.

! DANGERMOST TIRE WEAR IS CAUSED BY INCORRECT TOE SET-TINGS. NEVER CHANGE CAMBER OR CASTER SETTINGS TO CORRECT TIRE WEAR PROBLEMS. IF THE AXLE ASSEMBLY IS BENT TO CHANGE CASTER OR CAMBER, THE STRENGTH OF THE AXLE IS REDUCED AND THE WARRANTY IS VOIDED. AN AXLE DAMAGED BY BEND-ING MAY CAUSE A VEHICLE ACCIDENT AND RESULT IN SERIOUS PERSONAL INJURY.

1. Ensure the vehicle is on a level surface. Place blocks behind the rear wheels to prevent the vehicle from moving. Raise the vehicle so the front tires are off the ground.


2. Use jacks to raise vehicle so the front tires are off the ground. Support the front axle with safety stands.

3. Use paint or chalk to mark the center area of both front tires around the complete outer surface of the tire.

4. Place the pointers of a trammel bar on the marks of each tire. Rotate the tires. Make sure a straight line is marked on the outer surface of the tire.

NOTE: Do not measure toe-in with the front axle in the raised position. The weight of the vehicle must be on the front axle when toe-in is measured.

5. Lower the vehicle to the ground. Move the vehicle forward and backward 10 feet (3 meters).

6. Place the trammel bar at the back of the tires. Raise the pointers so they are level with the spindles. Align the pointers with the marks on the tires. Measure and record the distance between the pointers.

7. Place the trammel bar at the front of the tires. Raise the pointers so they are level with the spindles. Align the pointers with the marks on the tires. Measure and record the distance between the pointers.

8. To obtain the toe measurement, subtract the distance reading between the front of the tires from the distance reading between the back of the tires.

A DIMENSIONB B MINUS A EQUALS TOE-IN

A

B

FRONT OF VEHICLETOP VIEW

TOE-IN

Removal

20

9. If the toe measurement is not at the specifi ed distance, use the following procedure:

a. Loosen the tube clamp nut and bolt on each end of the cross tube.

b. Turn the cross tube until the specifi ed toe-in distance is obtained.

c. The threaded portion of the tie rod end must be installed into the cross tube beyond the point where the tube slot stops.

CROSS TUBE TIE ROD END

MARKSTUBE SLOT

BOTTOM VIEW

d. Tighten the nut and bolt on each end of the cross tube to 40-60 lbs. ft. (54-81 N·m).

10. Repeat Steps 1-8 to check the toe-in dimension.

Removal Removing the Wheel Ends


1. Ensure the front of the vehicle is raised until the front wheels are off the ground. Support the vehicle with safety stands.

2. Remove the capscrews fastening the cap to the hub. Remove the cap and the gasket.NOTE: When the adjusting nuts are tightened or loosened, always use the correct size socket to avoid damaging the nut.

3. Remove the fasteners for the wheel bearings. Use the following procedure for double nut and lock fasteners:

a. Bend the tabs of the fl attened lock washer away from the wheel bearing nut and the adjusting nut.

WHEELBEARING NUT

PIERCEDLOCK RING

ADJUSTINGNUTWHEEL BEARING

NUT LOCK WASHER

DOUBLE NUT AND LOCK ADJUSTMENT

b. Remove the wheel bearing nut, the lock washer, the pierced lock ring, and the adjusting nut from the knuckle.

4. Remove the outer wheel bearing cone from the hub.

5. Remove the wheel and tire and the hub and the drum as assembly.

6. Remove the brake components per manufacturer procedures.

7. Remove the oil seal from the hub. Remove the inner wheel bearing cone.

8. Inspect the wheel bearings. See "Tapered Roller Bearings" on page ix.

Removal

21

Removing the Drag Link


1. Remove the cotter pins from the ball studs.

2. Remove the nuts from the ball studs.

3. Disconnect the drag link from the pitman arm and the steering arm.

PITMANARM DRAG

LINKSTEERING

ARM

4. Inspect the drag link for damage or wear.

Removing the Steering Arm1. Remove the cotter pin and the nut fastening the

steering arm to the drag link. Disconnect the steering arm from drag link.

SAFETYSTANDS

STEERINGARM

2. Remove the cotter pin and the nut fastening the steering arm to the knuckle.

3. Remove the steering arm from the knuckle. If necessary, tap on the end of the arm with a leather or plastic mallet to separate the arm from the knuckle.

4. Remove the key from the steering arm.

5. Inspect the steering arm for damage or wear.

Removal

22

Removing the Tie Rod Arms, Tie Rod Ends, & the Cross Tube1. Remove the cotter pins and the nuts fastening each

tie rod end to the tie rod arms.

TIE ROD ARM

TIE ROD END

2. Disconnect the cross tube assembly from the tie rod arms. If necessary, use a removal tool to separate the tie rod end from the tie rod arm.

3. Remove the cotter pin and the nut fastening the tie rod arms in the knuckle.

4. Remove the tie rod arms from the knuckle. If necessary, tap on the end of the rod with a leather or plastic mallet.

5. Remove the key.

6. If necessary, remove the tie rod ends and use the following procedure:

CROSS TUBE TIE ROD END

MARKSTUBE SLOT

BOTTOM VIEW

a. Mark the position each tie rod end is installed in the cross tube.

b. Remove the bolts and the nuts from the clamp on the cross tube.

c. Remove the tie rod ends from the cross tube.

7. The rotating style clamp on cross tubes can be rotated for easier accessibility when removing the clamp bolt and nut.

CLAMP

BOLTAND NUT

8. Inspect the parts. See "Inspecting the Tie Rod Ends" on page 5.

Removal

23

Removing the King Pins & Steering Knuckle1. Remove the wheel ends.

See "Removing the Wheel Ends" on page 20.

2. Remove the air from the brake system.

3. Disconnect the air lines from the brakes.

4. Remove the brake assembly from the spindle. Refer to the brake manufacturer procedures.

5. Remove the tie rod arms and the steering arms from the knuckle. See "Removing the Steering Arm" on page 21.

6. Remove the capscrews fastening the king pin caps to the top and the bottom of the knuckle. Remove the caps and the gaskets.

KNUCKLE CAP

GASKET

7. Remove the threaded draw keys as outlined in the next section.

Removing Threaded Draw Keysa. Loosen the threaded draw key lock nut until the

top of the lock nut is even with the end of the draw key.

b. Use a brass drift and a hammer to hit the end of the draw key.

NUT

DRAWKEY

c. Remove the nut from the draw key. Remove the draw key from the knuckle.

! WARNING• TO PREVENT SERIOUS EYE INJURY, ALWAYS WEAR EYE PROTECTION WHEN PERFORMING VEHICLE MAIN-TENANCE OR SERVICE.

•USE A BRASS OR LEATHER MALLET FOR ASSEMBLY AND DISASSEMBLY PROCEDURES. NEVER HIT STEEL PARTS WITH A STEEL HAMMER. PIECES OF A PART CAN BREAK OFF CAUSING SERIOUS PERSONAL INJURY.

! CAUTIONFORCE MUST BE DIRECTLY APPLIED TO THE BOTTOM OF THE NUT AND THE END OF THE KEY. IF FORCE IS NOT DIRECTLY APPLIED, THE DRAW KEY WILL BE DAMAGED.

NOTE: If the bushings are not being replaced, perform the following to prevent damaging the bushings during king pin removal.

• Remove any fl aring on the drift that may touch the bushings.

• Wrap tape to a thickness of 1/16" (1.5 mm) on the end of the drift.

Removal

24

1. Use a brass drift and a hammer to remove the king pins from the knuckle.

If the king pin is hard to remove, use a hydraulic king pin remover.

KING PIN

! WARNINGWEAR GLOVES WHEN REMOVING OR INSTALLING SHIMS. THE SHIMS HAVE SHARP EDGES THAT MAY CAUSE INJURY.

2. Remove the knuckle from the axle beam. Remove the shims, the thrust bearing, and the seal from between the beam and the knuckle.

KNUCKLE

SHIMS(BETWEENKNUCKLE

AND BEAM)

THRUSTBEARINGAND SEAL

3. Inspect parts for damage or wear.

Removing the King Pin Bushings from the Knuckle1. Remove and discard the lower king pin seal.

KING PINSEAL

2. Turn knuckle upside down and remove the upper king pin seal.

! DANGEROBSERVE ALL WARNINGS AND CAUTIONS PROVIDED BY THE PRESS MANUFACTURER TO AVOID DAMAGE TO COMPONENTS AND SERIOUS PERSONAL INJURY.

3. Remove the old bushings as follows:

NOTE: Bushings can be removed using a hydraulic king pin remover.

a. Make a tool to remove the bushings.

2.5”(63 MM) SUITABLE LENGTH

DIMENSIONS FOR BUSHINGREMOVAL & INSTALLATION TOOL

1.992 ± .001”(50.596 ± .025 MM)

2.116 ± .001”(53.746 ± .025 MM)

b. Place the knuckle into a vise. Use a press with a 5-ton capacity. Make sure the knuckle does not move when the bushings are removed.

Preparing Parts for Assembly

25

c. Install the tool into the upper king pin bushing. Press the upper king pin bushing from the knuckle bore.

UPPER KINGPIN BUSHING

LOWER KINGPIN BUSHING

d. Turn knuckle upside down and install the tool in the lower king pin bushing. Press the lower bushing from the knuckle bore.

Preparing Parts for AssemblyParts InspectionCarefully inspect all disassembled parts before assembly. Refer to the following guidelines:

a. Inspect and replace any parts that are worn, cracked or damaged. Check for cracks using dye penetrant, magnetic fl ux, or fl uorescent particle testing methods.

b. Remove the old bushing from the knuckle. Measure the upper knuckle bore inside diameter at two locations. Always use a micrometer and a telescoping gauge when taking knuckle bore measurements. Some rounding of the top and bottom bore edges is acceptable.

Measure the bore in four positions and at two locations. The two locations must be 90° opposite from each other (see the illustration below). If the average measurement is more than the Knuckle Bore Maximum Diameter specifi cation in Table D on page 26, replace the knuckle.

1 Measure here, then rotate tool 90º2 UPPER BORE3 Do same down here4 And repeat here

MEASUREMENT PROCEDURE

Repeat this procedure for measuring the lower knuckle bore. Refer to Table D and verify the average inside bore dimension does not exceed specifi cations.

Measurements taken at either the upper or lower knuckle bores which exceed the Table D specifi cations, indicate the knuckle requires removal and replacement.

Preparing Parts for Assembly

26

Measure bushingbore in four positions

(90º opposed)

KING PIN BUSHING MEASUREMENT

c. Measure the king pin bushing inside diameter using a micrometer and a telescoping gauge for taking measurements.

If the average inside diameter measurement is greater than the King Pin Bushing Maximum Inner Diameter in Table D, install a new bushing.

Measure the inner diameter of the new bushing after installation and reaming. Measure the inner diameter of the bushing in four positions and at two locations. The two locations must be 90° opposite from each other. If the average measurement is more than the King Pin Bushing Maximum Inner Diameter specifi cation in Table D, replace the bushing.

d. Measure the inner bore diameter of the axle beam. Rounding at the top and bottom of the beam is acceptable.

Measure the axle beam bore at four positions, (see the Measurement Procedure illustration), and at two specifi c locations: 1/2" (12.7 mm) below the top of the bore & 1/2" (12.7 mm) above the bottom of the bore.

1 0.5” (12.7 mm)

3 0.5” (12.7 mm)

AXLE BEAM MEASUREMENT

2

1

3

2 Measure bore in four positions (90º opposed)

If the average measurement is greater than the Axle Beam Bore Maximum Diameter given in Table D below, the entire axle beam requires replacement.

Table D: Axle Wear Limits Specifi cations

Model Knuckle Bore Maximum Diameter

Axle Beam Bore Maximum Diameter

King Pin Bushing Maximum Inner Diameter

FS25 2.127" / 54.0250 mm

2.0030" / 50.8767 mm

2.0030" / 50.8767 mm

Installation

27

InstallationInstalling Easy Steer King Pin Bushings in the KnuckleWithout a Press

NOTE: On FS25 axles, the bushings can be installed with-out a press. Bushing service kits are available to install and ream the bushings.

Easy Steer bushings have an interference fi t in the knuckle bores and require a suitable installation tool for bushing installation.

2.5”(63 MM) SUITABLE LENGTH

DIMENSIONS FOR BUSHINGREMOVAL & INSTALLATION TOOL

1.992 ± .001”(50.596 ± .025 MM)

2.116 ± .001”(53.746 ± .025 MM)

1. Position the bushings into outer end(s) of the knuckle bore(s). Install to proper position using selected installation tool.

EASY STEERBUSHING

2. Ream the Easy Steer bushings using the procedure in the following section.

With a Press1. Install the top king pin bushing fi rst.

! WARNINGOBSERVE ALL WARNINGS AND CAUTIONS PROVIDED BY THE PRESS MANUFACTURER TO AVOID DAMAGE TO COMPONENTS AND SERIOUS PERSONAL INJURY.

2. Put the knuckle in a press, if used, so the top of the knuckle is toward the top of the press. Make sure tops of the bores are parallel to the top of the press.

3. Place new bushing in the upper knuckle bore.

4. Using installation tool, press start the bushing 1/8" (3 mm) into the upper bore. Release the pressure. Make sure the bushing is straight into the upper bore.

UPPER KNUCKLE 1/8”DEPTH INSTALLATION

INSTALLATIONTOOL

BUSHING

BUSHING

LOWER KNUCKLE 1/8”DEPTH INSTALLATION

5. On Easy Steer bushings, press the bushing farther to a depth of 0.352 to 0.382" (8.94 to 9.70 mm) below the top of the upper knuckle bore.

Installation

28

UPPER KNUCKLE (OUTSIDE)0.352-0.382” (8.94-9.7 MM)

BUSHINGS

LOWER KNUCKLE (OUTSIDE)0.352-0.382” (8.94-9.7 MM)

EASY STEER TYPE BUSHINGS

6. Turn the knuckle over so the bottom of the knuckle is up. Make sure the bore is parallel to the top of the press.

7. Place new bushing in lower knuckle bore.

8. Using installation tool, press start the bushing 1/8" (3 mm) into the lower bore. Release the pressure. Make sure the bushing is straight into the lower bore.

9. On Easy Steer bushings, press the bushing farther to a depth of 0.352" to 0.382" (8.94-9.70 mm) below the top of the lower knuckle bore (as viewed with the knuckle upside down).

10. Ream the bushings using the procedure in the following section.

Reaming the Easy Steer Bushings

! CAUTIONREAMING WITH A FIXED REAMER IS THE ONLY REC-OMMENDED PROCEDURE. NEVER HONE OR BURNISH THE BUSHINGS. THE BUSHINGS WILL BE DAMAGED BY HONING OR BURNISHING.

1. Place the knuckle in a vise with brass jaws.

2. Refer to Table E on page 29 for reamer tool dimensions.

3. Slide the pilot of the reamer through the top bushing until the reamer blades touch the bushing.

Push down lightly

REAMING UPPER BUSHING

4. Rotate the reamer with a light downward pressure. Do not apply too much force. Rotate the reamer smoothly.

5. After the reamer cuts most of the top bushing, make sure the tool does not drop to the bottom bushing.

Installation

29

Table E: Bushing Reamer Dimensions

Model

Lower Pilot Diameter Dimension “A ± 0.001"/0.0245 mm

Blade Diameter Dimension “B” ± 0.0005"/0.0127 mm

Upper Pilot Diameter “C” ± 0.001"/0.0245 mm

Lower Pilot Length Dimension “D”

Upper Pilot Length Minimum Dimension “E”

inch mm inch mm inch mm inch mm inch mmFS25 1.9850 50.4190 2.0005 50.8127 1.9950 50.6730 10.10 256.54 12.10 307.34

REMOVABLEPILOT OPTIONAL REAMER

2.5” (63 MM)

MATERIAL: HIGH SPEED STEELNUMBER OF BLADES: USE 10-14 BLADESCUT OF BLADES: RIGHT HAND CUT, LEFT HAND FLUTELENGTH OF BLADES: 2.50” (63.5mm)

BA C

DE = D + 2” (50.8mm) MINIMUM

6. After cutting the top bushing, guide the reamer into the bottom bushing. Repeat Steps 3-5.

Push down lightly

REAMING LOWER BUSHING

7. Slide the reamer out of the bottom bushing. If the reamer must be removed through the top bushing, rotate the tool in the opposite cutting direction.

8. Clean all material from the bushings.

Installation

30

Installing the Inner Knuckle Bore King Pin Seals1. Place the top of the knuckle in a vise with brass jaws.

The bottom of the knuckle must be toward you.

2. Place the seal in the bottom of the top knuckle bore. The lip of the seal must be away from the bore.

Both upper and lowerinside seal lips must

be away from bore

3. Place the end cap for the knuckle on top of the seal. Slide the king pin through the opposite knuckle bore. Use the king pin to install the seal.

KING PIN

CAP

For Easy Steer bushings, make sure the top of the seal is even with top of the knuckle.

MACHINEDSURFACE SEAL

BUSHINGKNUCKLEBORE

4. Turn the knuckle over in the vise. The jaws of the vise must hold the bottom of the knuckle, and the top of the knuckle must be toward you.

5. Place the seal in the top of the bottom knuckle bore. The lip of the seal must be away from the bore.

Both upper and lowerinside seal lips must

be away from bore

6. Repeat Step 3 of this procedure.

Installation

31

Installing the Knuckle to Axle Beam1. Clean the bores of the knuckle and the axle beam.

2. Install the seal on the thrust bearing.

On “cover”-type seals, install the seal over the open end of the bearing.

COVER

BEARINGRETAINER

SEAL TYPES

BEARING CAGE(OPEN SIDE UP)

SEAL

! WARNINGWEAR GLOVES WHEN INSTALLING SHIMS. THE SHIMS HAVE SHARP EDGES THAT MAY CAUSE INJURY.

3. Inspect the shims for any damage before installation, noting the following:

• Replace damaged shims with same size shims (or in combination) to allow the least amount of knuckle end play.

• If a new shim pack must be determined, select the amount of shims to give the least amount of end play.

4. After inspection, place shims on top of axle beam bore machined surface. Align shims for king pin installation.

5. Place the knuckle on the axle beam.

6. Place a pry bar between the steering arm boss and the axle beam. Lift the knuckle and slide the shim pack between the top of the beam and the knuckle. Make sure all the bores are aligned. If the bores are not aligned, the parts will be damaged when the king pin is installed.

PRY BAR

SHIM

7. Remove the pry bar.

8. Before installing the king pin into the top of the knuckle, be sure to note the following:

a. Apply the specifi ed lubricant to bottom half of king pin.

b. Before placing the king pin into the top of the knuckle, be sure the word “TOP” (which is stamped on the king pin) can be seen.

“TOP”

KING PIN

c. Rotate the king pin so the two draw key slots of the pin properly align with the draw key slots in the knuckle.

Installation

32

! CAUTIONNEVER FORCE THE PIN THROUGH THE TOP BUSHING OR THE SHIMS WILL BE DAMAGED.

9. Install the king pin into the top of the knuckle and through the area where shims are located.

! WARNING• TO PREVENT SERIOUS EYE INJURY, ALWAYS WEAR EYE PROTECTION WHEN PERFORMING VEHICLE MAIN-TENANCE OR SERVICE.

• USE A BRASS OR LEATHER MALLET FOR ASSEMBLY AND DISASSEMBLY PROCEDURES. NEVER HIT STEEL PARTS WITH A STEEL HAMMER. PIECES OF A PART CAN BREAK OFF CAUSING SERIOUS PERSONAL INJURY.

10. If required, use a hammer and a brass drift to apply direct force to king pin for seating it into the lower knuckle bore.

NOTE:

• DO NOT drive or tighten the draw keys into the knuckle until the end play is checked and adjusted.

• The FS25 model uses threaded draw keys.

11. Seat top draw key into front of beam. Seat bottom draw key in back of beam by striking with hammer and drift. Make sure keys align with slots of king pin. DO NOT install or tighten lock nuts before checking the knuckle end play.

12. Check the end play of the knuckle according to the following procedure.

a. Strike the boss of the knuckle with a rubber mallet to move the parts in position.

b. Turn the knuckle to the straight (forward) position.

c. Attach a dial indicator. Place the base on the knuckle. Place the tip on the center of the king pin. Set the dial indicator to zero (0).

MAGNETICBASE LOCATED

AT EITHER PLACE

Installation

33

! DANGERIF A HYDRAULIC JACK IS USED TO MEASURE END PLAY, USE TWO SAFETY STANDS TO SUPPORT THE AXLE IN THE REST POSITION. IF SAFETY STANDS ARE NOT USED, THE AXLE CAN FALL AND RESULT IN SERIOUS PERSON-AL INJURY.

d. Use one of the following procedures to measure the end play.

• Place a pry bar between the knuckle and the top of the axle center. Push the knuckle up and measure the end play.

• Place a block of wood and a hydraulic jack under the bottom of the knuckle. Raise the knuckle until the pointer on the dial indicator stops.

WOODBLOCK

e. Repeat Steps C and D with the axle in the full right and full left turn positions.

f. The end play must be 0.001-0.025" (0.025-0.635 mm) in all positions.

If the knuckle binds or zero (0) end play is measured, remove shims from the shim pack.

If more than 0.025" end play is measured, add shims to the shim pack.

! WARNINGUSE A BRASS OR LEATHER MALLET FOR ASSEMBLY AND DISASSEMBLY PROCEDURES. NEVER HIT STEEL PARTS WITH A STEEL HAMMER. PIECES OF A PART CAN BREAK OFF CAUSING SERIOUS PERSONAL INJURY.

! CAUTIONMAKE SURE THE DRAW KEY IS INSTALLED COMPLETE-LY OR THE LOCK NUT IS TIGHTENED TO THE SPECIFIED TORQUE. IF NOT INSTALLED CORRECTLY, THE KING PIN AND THE AXLE BEAM WILL BE DAMAGED.

NOTE: FS25 model uses threaded draw keys.

13. Install the draw keys by installing the lock nut and tightening to 30-45 lbs. ft. (41-61 N·m).

LOCK NUT

Installation

34

14. Install new gaskets and the caps on the top and the bottom of the knuckle. Install the capscrews and the washers and tighten to 20-30 lbs. ft. (28-40 N·m).

CAP

GASKET

14. Connect the tie rod arm to the knuckle using the pro-cedure in the following section.

Installing the Tie Rod ArmsNOTE: If a diff erent tie rod arm is installed (such as for increasing the maximum turn angle), the steering geom-etry is changed and may cause tire wear. Contact your AxleTech service representative.

TIE ROD END

KNUCKLETIE ROD ARM

1. Press the key in the slot in the arm.

2. Install the tie rod arm in the knuckle.

! CAUTIONTIGHTEN THE NUTS TO THE SPECIFIED TORQUE. IF THE NUTS ARE NOT TIGHTENED TO THE SPECIFIED TORQUE, THE PARTS WILL BE DAMAGED.

3. Install the nut on the tie rod arm and tighten to160-300 lbs. ft. (217-407 N·m).

4. Install the cotter pins. If necessary, tighten the nut slightly, increasing the fi nal torque value until the holes are aligned. NEVER loosen the nut to install the cotter pin.

Installation

35

Tie Rod AssemblyNOTE: The cross tube has right-hand threads on one end and left-hand threads on the other end. Make sure the ends are installed on the tube.

1. If removed, install the tie rod ends on the cross tube to the position marked during removal.If new tie rod ends are installed, thread the ends equally on the cross tube to the required length.

2. Install the nuts and the bolts in the clamps and tighten to 40-60 lbs. ft. (54-81 N·m).

BOTTOM VIEW

Tie rod end isinstalled past

cross tube slotTIE ROD

END

MARKSCROSSTUBE

TUBESLOT

3. The cross tube clamp can be rotated for easier access when installing the clamp bolt and nut. Tighten nut suffi ciently to engage the locking element of the nut with the bolt. The clamp and tie rod end must rotate freely. Make certain the clamp tab is fi rmly seated against the cross tube.

TIE RODEND

CLAMPCROSSTUBE

BOLT & NUT

4. Clean and dry tie rod taper and connect the tie rod ends into the tie rod arms. The threaded portion of the tie rod end must be installed into the cross tube beyond the end of the slot. Make certain the clamp tab is fi rmly seated against the cross tube.

5. Install the nuts on the tie rod ends and tighten to 160-300 lbs. ft. (217-407 N·m).

6. Install the cotter pins. If necessary, tighten the nut until the holes are aligned. NEVER loosen the nut to install the cotter pin.

7. Check and, if necessary, adjust the toe-in. See "Adjusting the Toe-In Specifi cation" on page 19.

Installing the Steering Arm

! CAUTIONTIGHTEN THE NUTS TO THE SPECIFIED TORQUE OR PART DAMAGE WILL OCCUR.

SAFETYSTANDS

STEERINGARM

1. Press the key in the slot in the arm.

2. Install the steering arm in the knuckle.

3. Install the nuts and tighten to 775-1450 lbs. ft. (1051-1966 N·m).


5. Lubricate the drag link end connecting to the steering arm. See "Ball Studs on the Steering Arm, the Tie Rod Arm Ends, and the Drag Link" on page 6.

6. Check for correct vehicle operation.

Installation

36

Installing the Drag Link

! CAUTIONTIGHTEN THE NUTS TO THE SPECIFIED TORQUE OR PART DAMAGE WILL OCCUR.

PITMANARM DRAG

LINKSTEERING

ARM

1. Connect the drag link to the steering arm.

2. Connect the drag link to the pitman arm.

3. Install the nuts and tighten to:

• 3/4"-16 size: 90-170 lbs. ft. (122-230 N·m)

• 7/8"-14 size: 160-300 lbs. ft. (217-407 N·m)


5. Lubricate the drag link. See "Ball Studs on the Steering Arm, the Tie Rod Arm Ends, and the Drag Link" on page 6.


Installing the Brake Components & Wheel Ends1. Install the brake assembly on the knuckle referencing

the vehicle manufacturer procedures.

2. If grease-lubricated wheel bearings are installed they should be lubricated now before the wheel and tire assemblies are installed, see "Grease-Lubricated Wheel Bearings" on page 7.

3. Install the wheel and tire assembly.

4. If oil-lubricated wheel bearings are installed, see "Oil-Lubricated Wheel Bearings" on page 6.

5. Install the outer wheel bearing cone in the hub.

6. Install the adjusting nut.

7. Adjust the wheel bearings according to the wheel end manufacturer procedures.

8. Install the cap and the gasket on the hub.

9. Install the capscrews and tighten to 20-30 lbs. ft. (27-41 N·m).

10. Lower the vehicle to the ground.



Torque Specifi cations

37

Torque Specifi cations

7

8

5

3 4

1

2

6

2

Item Description SizeTorque Range

lbs. ft. N·m

1 Steering Arm to Drag Link Nut3/4"-16 90-170 122-2307/8"-14 160-300 217-407

2 Knuckle Cap Capscrew 5/16"-18 20-30 27-413 Steering Arm to Knuckle Nut 1-1/4"-12 775-1450 1051-19664 Draw Key Nut 7/16"-20 30-45 41-615 Cross Tube Clamp Nut 5/8"-11 40-60 54-816 Tie Rod Arm to Knuckle Nut 1-1/4"-12 775-1450 1051-19667 Stop Screw Lock / Jam Nut 5/8"-18 65-85 88-1158 Tie Rod Arm to Tie Rod End Nut 7/8"-14 160-300 217-407

Troubleshooting

38

TroubleshootingCondition Cause Correction

Tires wear out quickly or have uneven tread wear

Tires have incorrect air pressure Infl ate tires to correct PSITires out of balance Balance or replace tiresIncorrect tandem axle alignment Align tandem axlesIncorrect toe-in setting Adjust toe-in to specifi ed settingIncorrect steering arm geometry Service steering system as necessaryExcessive wheel end play Readjust wheel bearings

Vehicle is hard to steer

Power steering system pressure low Repair power steering systemSteering gear linkage not assembled correctly

Assemble steering gear correctly

Steering linkage needs lubrication Lubricate steering linkageKing pins binding Replace king pinsIncorrect steering arm geometry Service steering system as necessaryCaster out of adjustment Adjust caster as necessaryTie rod ends hard to move Replace tie rod endsWorn thrust bearing Replace thrust bearing

Tie rod ends are worn and require replacement

Tie rod ends need lubrication Lubricate cross tube ends following the recommended maintenance schedule

Severe operating conditions Operate vehicle correctlyDamaged boot on tie rod end Replace boot

Bent or broken cross tube, tie rod end ball stud, steering arm or tie rod end requiring component replacement

Too much pressure in the power steer-ing system / pressure exceeds OEM specifi cation

Adjust power steering system to speci-fi ed pressure

Power steering system cut-off pressure / out of adjustment

Adjust power steering system to speci-fi ed pressure

Severe operating conditions Operate vehicle correctlyAdd-on power steering system not installed correctly

Correct the add-on power steering system installation

Worn or broken steering ball stud

Drag link fasteners tightened higher than OEM specifi cation

Adjust to specifi ed torque setting

Lack of lubrication / incorrect lubricant Lubricate linkage with specifi ed lubri-cant

Power steering stops out of adjustment Adjust stops to correct specifi cation

Worn king pins and king pin bushings

Worn or missing seals and gaskets Replace seals and gasketsIncorrect lubricant Lubricate axle with specifi ed lubricantAxle not lubricated at recommended maintenance schedule

Lubricate following the recommended maintenance schedule

Incorrect lubrication procedures Follow recommendation lubricationLubrication schedule does not match operating conditions

Adjust lubrication schedule to match operating conditions

Vibration or shimmy of front axle during operation

Caster out of adjustment Adjust casterWheel assembly out of balance Balance or replace wheels and/or tiresWorn shock absorbers Replace shock absorbers

© 2019 AxleTech International LLC. All rights reserved. AxleTech and AxleTech International are registered trademarks of AxleTech International LLC.All other brands and product names are trademarks or registered trademarks of their respective owners. Information supplied by AxleTech is believed to be accurate and reliable. AxleTech reserves the right, without notice, to makes changes in product design or specifications.

Customer Service 877-547-3907+33 (0) 4 77 92 88 92

Customer Service Fax877-547-3987

Email OE: [email protected]: [email protected]

www.axletech.com

ASM-0002E 05/19

fs25...service notes iii service notes this service manual describes the service and repair...

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