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[HTi]Johnson

Rear diff

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I was thinking today, I have a 4psd d/r range tranny in my car, I looked at the rear diff and it has a 3.7 ratio sticker on it. Is it supposed to be 3.7 or 3.9, for that tranny?

Before, I had the Auto tranny in it, and in 4wd at 45mph i would get a humming from the rear. It doesn't do it now...with the 4psd in there...maybe that's why the automatic died?

Thanks.

[HTi]Johnson

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The correct rear diff for a d/r 4speed is a 3.9 and the correct rear diff for a EA81 4wd Auto is a 3.7; you may have a misslabled rear diff if you're not binding with the current setup.

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In 4wd your rear wheels are trying to pass the fronts if you have a D/R and a 3.7 diff :banghead:

 

You'd probably hear your drivetrain trying to compensate for the difference in speed. Churping rear wheels?

 

You may be able to jack the car up and see if the front and rear wheel move the same speed in 4wd. :confused:

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binding....in 4wd going around a turn on concrete...does it feel like itsbraking when your wheels are turned all the way?

that's it, but if you've got the wrong diff in there, it'll do that when you're going straight

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I was thinking today, I have a 4psd d/r range tranny in my car, I looked at the rear diff and it has a 3.7 ratio sticker on it. Is it supposed to be 3.7 or 3.9, for that tranny?

Before, I had the Auto tranny in it, and in 4wd at 45mph i would get a humming from the rear. It doesn't do it now...with the 4psd in there...maybe that's why the automatic died?

Thanks.

[HTi]Johnson

 

That tranny is definately 3.9 and that's the diff you need. I'm surprised something hasn't busted yet....

 

garner

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