Oil leaking between oil pan and transmission

redbullet

YJ Enthusiast
Joined
May 11, 2021
Messages
276
Location
San Jose, CA
My 1992 YJ 2.5 is leaking oil between the oil pan and tranny. I already tightened the valve cover bolts and am aware of the rear main seal going on these. My question is whether I may actually be missing bolts on the bottom of the cover between the pan and transmission. I one bolt on the lower face of either side and each side has two holes on it. How many bolts does your yj 2.5 have here? See the pic for reference. Thanks, Rob

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This might be a tough one to answer as 1992 2.5 auto was not a factory combination. 2.5 didn’t get the auto until 1994. You sure it’s a 92?
 
Frame and tub are 1992, engine is 1993. Hmmm. I should rename it frankenjeep. Anyone with an auto tans know if bolts go in the holes pictured.
 
The reason I brought that up is because I wasn’t sure if you actually had a YJ transmission if it wasn’t a factory combo that you have in there.

This is pretty much all the FSM shows for 95. It doesn’t even show the bellhousing having as many holes as you have.

So now I have to ask. Do you have a lockup torque converter? Does it lock? Are you running a PCM from a 94-95? There are a lot of questions posed by a later auto being in an earlier year that did not have that option….

It’s hard to figure out how yours should be when it isn’t factory and doesn’t match the diagram for the later years that were factory. I’m sure it can be figured out with enough brainpower.

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just to make sure - it is leaking motor oil and not trans fluid, correct?

Since the PCM has to have the function for the torque converter lockup built in, and that PCM wasn’t available until 1994, I’m wondering what is controlling that trans. Anything from 1993 would be for a manual and would not be providing the TC lockup function. That trans almost guaranteed has to be from a 1994 or later due to the odd bellhousing pattern to bolt it to a 2.5 which was not available until again, 1994. If it’s a 1994 trans, then it would have the lockup converter on it. If the lockup converter is not being activated by the computer, then the converter could go bad from overheating. Basically where I’m going with this is trying to rule out a bad converter leaking from not being operated properly.

Obviously you can usually tell motor oil vs ATF, but something to make sure of nonetheless.