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YJ engine swap

Sephrion

NAXJA Forum User
Location
Missouri
looks like im going with a 4.6L junkyard stroker for my XJ and my bro has expressed some interest in a stroker for his YJ ('95 stock, 4 banger), right now im planning on selling him the 4.0L thats currently in my XJ after i get my stroker completed and in... so what transmission should he run with it and what mods would we/he have to do to get the XJ 4.0L to fit into the YJ's bay?
 
Your XJ's 4.0L will slide right in fitment wise. You will need a new computer and all te wireing for a 4.0L and motor mounts. His transmission (an AX-5) will not work with a 4.0L due to haveing a smaller spline count on the input shaft. The easiest swap over would be an AX-15 from either a YJ,TJ or XJ. The AX-15 is a real good trans., there are better however (NV3550, NV4500 bla bla bla) but they are not a "bolt in and go" type of swap and cost more too. He will also need to change his T-case to an NP231 from a 6cly Jeep, years 1990 and I belive are all 23 spline units wich is what he needs sence his T-case is a 21 spline.
 
the 2.5 motor mount are in a different position then the 4.0. The tranny (if manual) is an AX5 and is not considered very strong so a different tranny would be needed. If you use an AX15 that came behind the 4.0's then you will also have to change the input shaft on the NV 231 tcase as the AX5 has a 21 spline output and the AX15 has a 23 spline.

Smitty
Yeah, I'm a YJ guy :D
 
thanks tory... guess i should add that his YJ is a '95 with the manual and my XJ is a '94 with a manual (which doesnt mean much), just wonder if he'd want to get rid of that dana 35 while his jeep is under the wrench lol
 
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