You should run your engine then take a clean rag and wipe the rear of the head below the valve cover to see if the leak is coming from there. They leak there lots and it imitates a blown rear main seal.
I have never heard of different seals for that engine if it is the seal gone. They are two piece seals that can be put in by removing the oil pan. No need to remove the whole engine or tranny.
If they have 2 seals on the shelf they think fit, I would buy both and just return the wrong one. If they grumble about the return, go to a real parts store or even the dealer and just get the proper one to start.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >
I saw the link with the 2 lip seal. Thanks. It says it supersedes the one lip seal so it is likely the more modern one. Another link I found also says it is the same 2 lipped seal for the 4.0 engine now....
I am not sure that would be a good thing though because the modern engines seem to leak worse or earlier than the older engines. This gent has an 89.
I think I would buy both and use the same as what comes out unless it looks like a replacement also.
I have an '88 YJ, 4.2L/manual. I've been through this debacle 6 times now. Autozone kept giving me the double lip seal, until I pulled the original seal out of the trash can, brought it to them, and figured out it's a single. To me they look identical, but I've only had success with the single lip. It's fel-pro part BS13879. Double lip seal is kind of a reddish/tannish color. Single lip is black. Yeah. I've done this a few times before. And make sure you don't shred the upper half of the seal putting it in, that's the other thing I had problems with. Bottom of my engine is now dry with the single lip. Good luck.
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