24 GEARS March 2002

ASK THE EXPERTS

W ell frustrated, would youbelieve the computer gener-ates this problem, and the

fix for this is reprogramming the com-puter with a new calibration?

WHAT?

That’s right, the computer signals theEPC to supply oil to the boost side ofthe pressure regulator circuit. If youpressure test the system and the pres-sures are not within the specifications(70-100 at idle and 245-290 at stall)then a reprogram is the fix.

For the vehicles that have this

problem you’ll see the idle pressure at90 or so, but when you accelerate thevehicle to back up, the pressure will notrise and the clutches will begin to slip.Here is the interesting part, the clutchesact like a support for the stamped steeldrum. When the clutches are appliedthe drum is stationary and the plane-taries are under tremendous stress.Under normal circumstances thatwouldn’t matter, however in this case,with slipping clutches, the drum startsto distort. The planet wants to turnalong with the sun gear and the ringgear. The problem occurs when theclutches don’t hold the drum stationary

and the planet starts to twist in the drumcausing it to distort, eventually poppingoff the snap ring; from there it’s history. Now you can do two things here to fixthis problem: REPROGRAM or Installan early design Low/Reverse set upfrom an E4OD (figure 1).

For more great fixes like these besure to attend the 2002 ATRA SEMINAR and get some key tips onkeeping all your units out for good…

The Experts

Figure 1

Ask

the

Exper

ts

Dear Experts,

I have a 1999 Ford F-250 with

the 4R100 in my shop for the

third time. It’s the same thing

every time…the Low/Reverse

snap ring pops off and the plan-

etary, drum and clutches are all

destroyed. The last time, it

didn’t even leave the shop.

What can I do to keep this unit

out?

Signed

Frustrated on the bench

2 FL. OZ. (59.25 ML)

S Y N T H E T I C

TESTED AND PROVEN

Part #3800

MADE IN USA

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Life Automotive’s

New Products for 2002Researched... Tested... Proven

Life Automotive Products inc. Memphis, TN 38103

2 FL. OZ. (59.25 ML)

S Y N T H E T I C

TESTED AND PROVEN

Part #3800 MADE IN USA

INSTANT®

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