Need help trying to put a 4.3 and auto tranny into a 85 XJ. Is there any differance between a GM and Jeep 231? It seems like a very easy swap, I'm guessing a 700r4 out of a S truck would work, however this creates an issue sense this engine is non computer controlled and I'm not sure how to hook up an OD tranny to it. Any help would be GREATLY apreciated. And I did a search

GM used non electric 700r4's until 93' ( not 100% sure on that year). They shouldn't require any type of tie-in to the engine computer. The transfer case adapter should bolt to your 231 also.

pick up the July issue of JP magazine has an article about doing a 700r4 swap, they did it in a TJ. According to the article, get one from a 87-92 1/2 or 3/4 ton truck, and i think the only difference is MAYBE the input shafts.

Thanks for the responces guys, exactly what I thought but wasnt sure about how the tranny was controlled.

The earlier 700R4's will only have a TV cable that will hook right up to the 4.3 The outputs on the tranny should be 27 spline if i am correct. Summit sells a 700R4 lockup converter kit for control of the converter on non computer controlled trannies.

The GM and Jeep 231 cases use a different front housing, you'll find that out when you try to bolt your six bolt Jeep case to the five bolt GM adapter, but you can use a GM S-10 case, look for a later model 231 rather than the early 207, you can get a SYE kit for the GM 231 through JB conversions, but I sould be with a little investigation, you could put together a GM/Jeep Hybrid t-case, they use a lot of the same parts, but not all. Make sure you use a 700R4 that is at least '88 and up, larger input shaft and some other updates, you can get a GM vacuum switch to lock up the converter, and wire the harness to you brake lights for the converter un-lock, you don't want to hit the brakes and stall your motor.