BY PAUL WEISSLER

Things are popping this year in light truck land, with new models and plentyof safety, performance and convenience upgrades for existing models.

22 January 2003

SERVICING THE

NEW LIGHT TRUCKSFor 2003, there’s a fresh crop of SUVs (and one

truck) from the U.S., Europe and Asia—and Asiadoesn’t mean just Japan anymore.

The U.S. offers the new Ford Expedition and Lincoln Navigator and Aviator, GM’s Hummer H2and the Chrysler Group’s hemi-powered heavy-duty Dodge Ram pickups. Europe is sendingthe Volvo XC90 and the British-built (BMW-powered) Range Rover. Japan has modelsfrom its Big Three—the new Toyota

For 2003, there’s a fresh crop of SUVs (and onetruck) from the U.S., Europe and Asia—and Asia

doesn’t mean just Japan anymore.The U.S. offers the new Ford Expedition and

Lincoln Navigator and Aviator, GM’s Hummer H2and the Chrysler Group’s hemi-powered heavy-duty Dodge Ram pickups. Europe is sendingthe Volvo XC90 and the British-built (BMW-powered) Range Rover. Japan has modelsfrom its Big Three—the new Toyota

Dodge Ram

23January 2003

Lincoln Navigator (background) & Aviator

Honda Element

Volvo XC90

4Runner and Lexus GX 470, the HondaElement and the Nissan Murano. Addthe Kia Sorento to the ’03 list, whichjoins the Hyundai Santa Fe, introducedlast year. These two Korean productshave been changing a lot of minds.

We know there’s more in thepipeline, too, with Nissan ready to showus the Pathfinder replacement thismonth, a new GMC SUV based on theEnvoy coming a bit later, plus all-newGM compact pickups and the 2004Ford F-150. Even Porsche will soonbring its Cayenne SUV to these shores.

The efforts to improve SUV stability

are ongoing, of course. Volvo has madethe most impressive moves, with its gy-roscopic stability control. However,both Range Rover and Toyota/Lexus,with their hydraulic cross-linking of theshock absorbers, also have significantnew technology.

So here’s a rundown on the newestSUVs and light trucks now—or soon tobe—on U.S. highways.

TOYOTA/LEXUSA brand-new 4.0L V6—Toyota’s firstall-aluminum truck/SUV engine—iscoming for the new 4Runner and its

upscale Lexus cousin, the GX 470, thiswinter. It’s a slightly long-stroke engine(94mm bore x 95mm stroke). Com-bined with variable intake valve timing,it produces 282 ft-lb of torque at 3800rpm (245 hp at 5200). It’s a very livelyengine that actually produces morehorsepower than the V8 (235), but lesstorque (the V8 delivers 320 ft-lb).

The V6 block has an open-deck de-sign with siamesed bores, but there’s awater passage between them. The cylin-der liners are very thin and not recom-mended for a rebore, so long down theroad they’ll have to be resleeved. Themain bearing caps are held by four“plastic region” (torque-to-yield) boltsfrom underneath and two bolts thread-ed in from the sides.

There’s a dual oil pan design—a mainaluminum casting (for structural rigidi-ty) and a steel pan as a secondary reser-voir to provide needed oil capacity.Cheers to Toyota for the oil filter, whichis surrounded by a bracket shaped likepart of a funnel. Attach a hose to thepipe on the bracket, loosen the filterand the oil flows through the pipe andhose into a drain container.

The clutch-type fan has a thermostat-ic bimetal valve that provides three-position control of the silicone fluidvalve inside the coupling—off and lowand high speeds.

The intake air chamber is a plastichousing with a solenoid valve actuatorto provide two airflow paths based onengine rpm. That actuator is laser-welded onto the chamber, so if it everneeds replacement, we hope there’ll bea field service kit that allows you toavoid installing an entire chamber.

The 4Runner and Lexus GX 470share the same 4.7 V8 and Torsen(torque-sensing) center differential4WD system, although each has differ-ent controls. Surprisingly, the more lux-urious GX 470 has the “rugged” 4H-to-4L shift lever, while the 4Runner has anelectrical control system with a dash-board knob.

The 4Runner/GX 470 cross-linkingof the shock absorbers is a diagonal set-up, somewhat like hydraulic brakes.Midpoint in the hydraulic line betweenone front and the opposite rear shock isa “center absorber.” When the vehicle

24 January 2003

SERVICING THE NEW LIGHT TRUCKS

The new Toyota 4Runner’s base engine, a 4.0L V6, has an open-deck block de-sign with siamesed cylinder bores. A drilled coolant passage (red arrow) inthe siamese joint prevents a hot spot from developing.

The curved bracket under the 4.0 V6’s oil filter is shaped like a funnel. All youhave to do following an oil filter replacement is remove the cap from the pipeend and attach a drain hose and oil flows neatly into a container.

Drain PipeWith Cap

Oil Filter

Oil Filter Bracket

starts to tilt, the shock in compressiontransfers pressurized fluid to the centerabsorber, and through it to the extend-ing shock, increasing its damping force.

FORD EXPEDITIONLINCOLN NAVIGATORThe two full-size Ford SUVs are all-newmodels for ’03, featuring rack & pinionsteering, four-wheel-vented disc brakesand independent rear suspension, withaxle shafts passing through slots in theframe, a design pioneered in the Ex-plorer. But there are also lots of techni-cal differences between the Expeditionand Navigator.

The Expedition’s base engine is the

SOHC 4.6L V8, which has the samehorsepower as in ’02 (232 horses), but anew torque curve that peaks at 291 ft-lb. However, the engine block is an all-new aluminum casting, and many en-gine internal parts were redesigned.

The Expedition offers a 5.4L V8, butit’s also a SOHC, with a new stiffer andquieter cast-iron block rated at 260 hp,with a reworked torque curve thatpeaks at 350 ft-lb.

The Navigator has just an iron-block5.4 V8, but it’s a DOHC version rated at300 hp, also tuned for torque (355 ft-lbat 2750 rpm). Its engine-mounted fan iscontrolled by an electromagnetic clutch.

The Expedition’s suspension is coil

spring on 2WD, torsion bar on 4WD,compared with air suspension on allNavigators (but a forthcoming optionon Expedition).

The Expedition/Navigator 4WD hasa new Control Trac system, whichbrings a true 2WD position, while alsoproviding all-wheel drive, 4-High and 4-Low. In 2WD, the system disconnectsat each front wheel hub, not merely atthe front axle, so the axle shafts andgears are motionless. That helps im-prove fuel economy. The wheel hub dis-connect is a next-generation version ofthe Warn vacuum chamber system thathad been used on Ranger pickups.

There are lots of electronically con-

trolled features on these vehicles. Theoptional running boards on the Naviga-tor, for example, are not some simpleswitching setup. They stay deployed un-til the vehicle is moving at least 5 mph.For reliability, all wiring and bearingsare sealed against moisture, and thetrack is a self-cleaning design.

There are a powered liftgate, option-al power-folding third row seat backs,even power folding side mirrors (whichare heated, by the way).

Late in the model year you can alsolook forward to optional tire pressuremonitoring—a direct-reading systemwith an on-board receiver/computerand a transmitter in each wheel. The

transmitter, which identifies thewheel, is built into the tire valve, so atire change is no longer a simple “re-place the valves” matter. Those partsare 1. not going to be cheap and 2. spe-cific to the wheel, so you can’t usejust any one. As for tire rotation, wemight have to look forward to repro-gramming. There are other types ofin-wheel transmitters, separate fromthe tire valve, but they’d complicateinstallation of accessory wheels.

LINCOLN AVIATORThe Aviator is built off the Ford Ex-plorer platform, and looks much like aNavigator that got shrunk. So it’s nosurprise that it has a DOHC version ofthe 4.6L V8 (vs. the DOHC 5.4L V8in the Navigator). There’s no shrink-age in horsepower; in fact the 4.6 V8all-aluminum design develops 2 morehorses (302), though significantly lesstorque (300 ft-lb vs. 355 for the 5.4 V8in the Navigator).

The Aviator’s brakes resemble thosein the Explorer. They’re twin-pistoncalipers over vented discs in front, sin-gle-piston over solid discs in the rear.However, the brakes are significantlylarger than the Explorer’s, so you can’tdo any parts swapping.

There’s a 2WD model Aviator, but noControl Trac 4WD. Instead, an all-wheel-drive option, similar to what’sused on the Mercury Mountaineer, isavailable.

As with the Aviator’s bigger brothers,direct tire pressure monitoring will bean option, late in the model year.

RANGE ROVERThere were many snickers about theRange Rover’s 4.0 and 4.6 V8s beingbased on a 40-year-old GM engine, butthat was a distortion of history. Thecylinder bore spacing may have beenunchanged, but the engine has beenmodernized repeatedly over the years.The pushrod engine, still available onthe Rover Discovery, is all-aluminumand develops a respectable 217 hp and300 ft-lb of torque.

When BMW bought Rover (which itlater sold to Ford), it began engineer-ing a new model. So the 2003 RangeRover is a BMW design, including a

25January 2003

Cross-linking of shock absorbers with fluid tubing and a “center absorber”improves vehicle stability on the Toyota 4Runner and Lexus GX 470. The shockunder compression transfers pressure through the center absorber to theshock on extension, to increase its damping force, reducing body tilt.

FrontShockAbsorber(LH)

CompressingExtending

RearShockAbsorber(RH)

Center ControlAbsorber

Orifice

specific version of the BMW 4.4L V8engine. The V8 produces 282 hp and325 ft-lb of torque at 3600 rpm. It hasvariable valve timing on the intakevalves only.

Is this engine a specific version?Yes, it ’s tuned for more low-endtorque, and it’s been “ruggedized,”with such things as super-sealing ofoil and coolant passages and accesso-ry bearings well-sealed against waterintrusion. Another upgrade is that thebelt pulleys have protective/retainingridges at the inboard and outboardends so debris is kept out and the

ribbed belts stay in their grooves.The suspension is independent all

around, with air springs, of course. Theshock absorbers are cross-linked, butstraight across (front to front, rear torear).

The Range Rover’s AWD drivetrainhas a two-speed electronic transfercase that has a Torsen differential toregulate torque transfer between frontand rear. The setup is combined withtraction control so the vehicle is fullycapable off-road, while providing bind-free operation even in tight turns.

At a price in the neighborhood of 70

grand, Range Rover isn’t cheap, butwith its combination of fine interiormaterials, overall elegance and lead-ing-edge engineering, it’s fully compet-itive with anything in its class.

DODGE ‘HEMI’The hemi is back, sort of. The ChryslerGroup has introduced an all-new 5.7LV8 with a combustion chamber veryclose to the hemispherical design of itshigh-performance engines in the ’50sand ’60s. But this one is a truck engine,and although it started out in theheavy-duty Dodge Rams, it also is go-ing into the light-duty Rams.

The hemi replaces the 5.9L V8,which is on phaseout (so you’ll still seeit in some Jeeps and early light-dutyRam pickups, for example). The hemiis a two-valve pushrod engine, withtwo spark plugs per cylinder, firedfrom an eight-coil bank. Because it’s awaste-spark system, you eventually canlook forward to replacing 16 sparkplugs and wires.

The engine itself is a deep-skirtedcast-iron design with cross-bolted mainbearings. The top of the hemi is cov-ered by a giant Siemens-built plasticair-fuel module/manifold that holds theelectronic throttle, air filter and fuel in-jectors.

The 5.9L Cummins turbodiesel re-mains very much in the picture. Intro-

26 January 2003

SERVICING THE NEW LIGHT TRUCKS

Left: This looks like a conventional tire valve from the outside, but it’s actually part of a tire pressure monitoring sys-tem that will be introduced late in the model year on the Ford Expedition and Lincoln Navigator. Right: A look insidethe tire shows the inner part of the valve. It’s a small transmitter that sends tire pressure signals to an on-board re-ceiver and electronic module for display on the dashboard cluster. Extra care during tire changes seems in order.

This vacuum-actuated wheel hub is installed at each front hub on the new Ex-pedition/Navigator 4WD, to provide a disconnect at the wheel. The front axleshafts and gears are motionless in 2WD, improving fuel economy.

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duced in 1989, it’s a solid seller (in fact,the primary choice for heavy-duty).For 2003, this DOHC, 24-valve inlinesix has been extensively reworked; 300of its 370 parts are new, including thehead and block. It’s upgraded to thecommon-rail high-pressure electronicfuel injection system that improvesidle, fuel economy and combustion(lowering emissions). Along with otherchanges, the engine now gets a 15,000-mile oil change interval, which is dou-ble the 2002 spec. Horsepower is upfrom 245 to 305 and torque from 505to 555 ft-lb.

The Cummins diesel in ChryslerGroup applications uses the Chryslerhybrid coolant, which is a combinationof silicates and organic acid inhibitors.

HUMMER H2The new Hummer H2 is not really a“baby” version of the Hummer H1. It’sjust over 5 inches narrower, but at 190inches overall, it’s actually 5 incheslonger (and a couple of inches taller).Built on a modified Chevy Tahoe/GMC Yukon chassis, the H2 is pow-ered by the 6.0L GM Vortec V8, whichdevelops 316 hp and 360 ft-lb oftorque, vs. 195 hp and 430 ft-lb oftorque for the military-based H1. Andat 6400 pounds, the H2 is 750 poundslighter than the H1.

The 4WD system on the H2 uses aBorg-Warner two-speed electronicallycontrolled transfer case, comparedwith a Torsen design in the H1. TheBorg-Warner case has no clutches orbands, but a pair of planetary gearsetswith gears moved by shift forks. Thefront planetary setup provides either1:1 or 2.64:1 gear reduction. The rearsetup uses a chain drive with gearingthat provides a 40% front, 60% reartorque split. If the driver engages ashift collar, the front and rear axles arelocked together, so torque goes to theaxle with traction.

In addition, there’s an Eaton elec-tronically locking rear axle, for extremeside-to-side slippage situations. Theengineers liked it so much, they decid-ed to put it in the H1.

The H2 has a torsion bar indepen-dent front suspension and a five-linkrear with a variable-rate coil spring (an

air spring is an option). It may lack theindependent rear suspension of theH1, but the ride is far superior, and theH2 can climb over 16-inch rocks (yes,

we did it). Ground clearance is 10 to12 inches, and the 17-inch wheels hold35-inch tires.

Although the H2 is engineered and

27January 2003

The Dodge hemi V8 has two spark plugs per cylinder fired from an eight-coilbank and a nearly hemispherical combustion chamber, all of which improvethe combustion process for more power. The all-new engine is a two-valves-per-cylinder pushrod type, a design that still finds many applications.

marketed by GM, it’s built in a specialplant under the supervision of AMGeneral, the maker of the H1. At about$50,000, the H2 is less than half theprice of the H1 (about $112,000). Iteven has such safety niceties as four-channel ABS and air bags (not found onthe H1).

GM for 2003 is more than the Hum-mer H2. The 5.3 Vortec V8 goes to all-aluminum construction, the first step inan extensive redesign of the Vortec se-ries that will hit stride at the end of nextyear and include “displacement on de-mand” (cylinder bank deactivation un-der low loads, for fuel economy). The5.3 V8 gets an oil pan with a “pass-through” opening, so it can be used on4WD models, such as Chevy Trailblaz-er/GMC Envoy, which currently haveonly the 4.2 I6.

Four- and five-cylinder spinoffs fromthe 4.2L I6 also will be introducedshortly. The four will be 2.8 liters, thefive 3.5 liters, and they’ll go into all-newcompact pickups, to be named ChevyColorado and GMC Canyon.

The zoned electronic architecture in-troduced on the Trailblazer/Envoy(modules in the engine compartment,dashboard and rear) will be phased inon all 2003 GM light-duty trucks andSUVs. The architecture, a vehicle com-puter network, permits substantial re-

ductions in wiring. A typical door, whichpreviously had 40 wires, now has only16 in the zoned arrangement. However,comprehensive diagnostics for thezones require a scan tool with suitableGM body computer software.

VOLVO XC90A Volvo in an SUV/truck report? Well,Volvo is known for its Class 8 big rigs(now a separate company not ownedby Ford). But the SUV market is so

huge that Volvo had to enter, using amuch-reworked version of the largefront-drive passenger car platform.

Volvo has two images it projects—safe and “green”—and the XC90 hasbeen designed to attend to both. It’sthe first SUV with both advanced anti-rollover engineering and a body thatcan roll over and over and over andend up with just minor sheet metalcreasing.

The antirollover system features agyroscopic sensor that can preciselymeasure roll speed and angle. If itsenses risk of rollover, the stability con-trol electronic module reduces enginepower and applies specific wheelbrakes to stop the vehicle and put it in-to an understeer.

Of course, any vehicle can roll overif the situation is severe enough, suchas a side impact from another car orhitting an angled surface. If the XC90does roll over, its ultra-high-strength(boron) steel structure keeps the cabinintact. MOTOR witnessed a test at theVolvo Safety Center in Sweden, and af-ter a triple-plus rollover, a fracturedcontrol arm and the aforementionedsheet metal creasing were the worst ofit. The interior air bags and side cur-tains protected the crash dummiesvery well.

The XC90 has a third seating row. Inaccordance with Volvo’s safety image,

28 January 2003

SERVICING THE NEW LIGHT TRUCKS

A one-piece plastic housing covers the top of the Dodge hemi V8. It includesthe air filter and intake, electronic throttle, fuel injectors and intake manifold.

The new Cummins 5.9L I6 diesel gets a “common rail” high-pressure fuel in-jection system, which has two-stage injection—a pilot burst to start combus-tion and a larger burst to continue the power stroke. Engine performance isup from 245 to 305 hp and from 505 to 555 ft-lb of torque.

Common Rail

its presence was factored into the safe-ty equation—leaving enough space be-hind the seats for a crumple zone—incase the vehicle is hit in the rear.

The XC90’s engine is the twin-turbo2.9L inline six, the only transverselymounted one of its type. It now hasvariable valve timing on both the in-take and exhaust, a combo that primar-ily reduces emissions, to help with the“green” image. The vehicle also has thePremair-coated radiator that Volvolong has used to “eat” ground-levelozone. It really doesn’t do much forthe cost of the catalytic coating, butwhen you’re green, you do almostwhatever works.

The engine still has a timing beltdrive, which is intended to keep theengine quiet. The battery didn’t fit intothe compartment; it’s in the back of thevehicle, under a cover plate close tothe bumper.

The AWD coupling on the XC90 is anew Haldex design. When there’s aspeed difference between front andrear axles, a piston proportionally ap-plies a multidisc clutch pack, to trans-fer torque to the rear. The Haldex cou-pling has a small DC electric motorthat pressurizes the coupling, so whenthere’s slippage, the torque transfer isinstantaneous—1⁄7 of a wheel turn.There are two filters in the coupling, aprimary pleated paper filter and a

coarse screen (to minimize flow re-striction at low temperatures) just forthe chamber at the electric motor.

HONDA ELEMENTThe new Element is very boxy, theo-retically designed for a college-agecrowd that needs lots of interior roomand a hose-washable floor. However,it’s also a suitable small business van,whose doors open to reveal a cabinseemingly without B-pillars. Actually,

B-pillars are built into the ends of thedoors, which latch into the floor railsand roof. Under the skin, the Elementis a carlike Honda CR-V, so it has anoptional AWD system. Carrying a pricetag of $16,000 to $20,000, it’s certainlyaffordable.

KIA SORENTOThe Sorento is just upscale of theHyundai Santa Fe (a few inches longerat 180 overall), and more powerful, witha 3.5L V6 that produces 192 hp. Thiscompares with the Santa Fe’s standardfour-cylinder and optional 2.7L V6 thatproduces 173 hp. The Sorento comes in2WD and part-time 4WD versions, andis priced at $20,000 to $25,000, a coupleof grand over the Santa Fe. That givesthe Hyundai Group (which owns Kia)nice coverage of the lower end of thebody-on-frame sport/ute market.

What we’ve given you here are justthe highlights of what’s available now.As we said at the start of this report,there’s lots more on the way. Comingsoon, to a highway near you.

29January 2003

This closeup cutaway shows the gerotor pump that pressurizes the couplingin Volvo’s XC90. It’s operated by the DC electric motor at right. A coarse whitescreen provides added protection from any contaminants in the oil.

This cutaway of the XC90 torque transfer coupling (located just forward ofthe rear axle) shows the paper filter and the multidisc clutch.

Filter

Screen

Gerotor PumpDC Motor

Multidisc Clutch

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