I just bought an 86' Comanche with the 2.8L v6 carb. I would like to swap in a I6 out of a 92 or older Cherokee. How hard is this task. Can the 5 speed tranny handle it or is there a kit I'll need to get? Or maybe just move the motor mounts and everything else is a bolt in? If someone knows of a write up on this subject already and could post it that would be greatly appreciated. Thanks.

 

You will have issues with the I6 fitting in the V6 engine bay. On the XJ the engine bays are all the same, but on the MJ it was different for the I4, I6, and V6. You will have to make modifications to the firewall. The best engine swap option for the V6 MJ would be to find a 3.4 Chevy engine and transplant it.

 

Would the 3.4 require mount mods or is it a bolt in? I don't really have access to a welder, and I'm a disabled vet on disability so I can't afford to pay someone to cut and weld for me.

 

I did a search online and found that the 2.8, 3.1, and 3.4 are all 60 degree V6 GM engines based on the same block. This should be a direct bolt in swap. Research also shows that the bell housing configuration limits that transmission options that can be used to upgrade for lower gears and larger tires.