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JrodNJ 06-11-2011 11:27 PM

What year 4.0's can I swap into my 1994 Wrangler?

New forum member here. I've owned 2 YJ's in the past (both 4.2's) and just picked up a 1994 4.0 5 speed Wrangler. Well, the "misfire" in the motor turned out to be a bunch of collapsed lifters due to a suspect oil pump.

Instead of rebuilding it seems like the best course of action is to find another running Jeep to scavenge the motor from. I am thinking a 4.0 Cherokee or Grand Cherokee is the way to go.

What year motors can I use for this? I want to do a direct swap without headaches. I do not want to get any sort of odd ball or performance upgrade; I just want to get plug and play and get back on the road for the summer.

I assume the latest motor I can get is a 1995? Is that correct? What is the earliest 4.0 motor I can go with? Anything to watch out for on certain years?

1988 - 1995, or should I look for a 1991 and up?

Also, does it make a difference what transmission is in the donor vehicle in terms of plopping it into my Wrangler?


JrodNJ 06-12-2011 07:32 PM

Bump for the Sunday Night crew; 91-95 seems the way to go?

banks316 06-16-2011 01:16 AM

Any 4.0 should work either out of a yj or xj. Just make sure that if you have a high output you replace it with a high output . Same goes with a non high output.

crafty 06-16-2011 09:11 AM

I have a 93 on it's 3rd engine now. First replacement was a 96 Cherokee 4.0 and the new one is from a 99 TJ. No newer than a 99 will work without some extra headache.

You will need to change the pilot bearing which can be a pain when you swap engines.

Leans93 06-16-2011 10:30 PM

For sure you want 91 and up as they are the HO motors. The 90 and older are Renix and not the same motor. Also you can pull one from a YJ XJ or ZJ as I know 91-95 the long blocks are identical. Also it doesn't matter what tranny is behind it.

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