ive heard that most things are the same from a 84 to a 01 jeep but i was wondering if i could switch a automatic engine from a 91 in the currently configured manual transmission of my 86. the 86 has a 2.4 with 4x4 and the auto is from a 4.0 with 2wd. if anyone can help i would appreciate it. the other option is to swap engines too tho.

 

I might be wrong, but I think the 2.5 4 cyl. and the 4.0L 6 cyl. use a different bolt pattern on the trans. If this indeed is the case, then the trans.'s will not interchange. I've been wrong before though. JMO

 

You have a different firewall than an 01 so the 4.0 wont fit unless you fab. the firewall. and you may need to kae the computer from the 01 also. Thats if you decide to swap engine and tranny.