Expert Advice Needed, Engine/Trans Swap
 

Hello gals and guys, been a long time.

My 1990 Cherokee is running strong, but the seat is about fall through the rusty floor.

I found a rust free 1984 Cherokee with no motor, trans or transfer case, and my son has voluteered to help do most the swap (after I mentioned all the food he ate for the 1st 18 years of his life) . Now before I buy, I need to make sure everything from my 1990 4.0 will fit without a lot or any mods.

Any help would be greatly appreciated.

I may be mistaken but I may also not be but I do believe that the 84 and the 1990 have different dimensions which could mean a slightly larger or smaller compartment for the engine and its core components. Do you know what the dimensions are for both jeeps? Again I could be wrong but better to know than assume.

^your wrong.

84-01 Cherokees have the same dimensions.

However with the 84 not originally having a 4.0L since they were only offered with a 2.5L 4cyl or a 2.8L V6 from 84-86(i believe) and 87-90 having Renix era 4.0L I6's and 2.5L 4cyl offered.

The "frame" side motor mounts will be completely different between the 1984 and the 1990 as will the transmission cross member. So you will have to cut the motor mounts from the frame side of the jeep out of the 90 and weld them into the 84, and use the transmission cross member from the 90 as well. You would probably be better off finding an 87-90 Cherokee for a transplant candidate because it would be a ton easier.

wouldn't that mean that the 84s firewall is not far back enough for the 4.0? Since it was prior to the firewall being moved back more so the 4.0 could fit in 1987.

no they are all the same dimensions, the motor mounts are in different locations on the "frame"

Makes sense, I'm going with ^ and saying that you would have a easier time with a 87-90 swap.

Thanks guys, I appreciate the feedback. I had some hope on this, but am thinking the project is above our means and abilities after reading this. I will continue to look for a good roller here in MI, or a decent buy on something in better condition than my current ride.

how bad is it?