Cherokee To Comanche Drive Train Swap

[Avandergriff]

I have a 1989 2.5l 2WD swb Comanche that has nearly 300,000 miles on it. The motor and transmission both  need to be rebuilt. I have found an 1986 Cherokee that also has the 2.5L inline 4 but is 4wd with a 5 speed manual. Would there be any major problems i might encounter when it comes to swapping the entire drive train (Engine, transmission, transfer case, & front axle) from the Cherokee to my Comanche?

[Geonovast]

Everything will swap right over if you currently have a 5 speed.

 

If you have a 4 speed, the axle ratios won't match, so you'd either need a different front axle or to move the XJ rear axle over (requires welding on new perches).

 

If you have an auto, it's going to be a little more work.

 

Regardless you're going to need to have your rear driveshaft shortened.

[Avandergriff]

its a 4 spd manual right now. so i would have to do both front and rear axle swaps? i assume since i would have to have the drive shaft shortened the two wheelbases are different? Also the wiring harness around the battery of the donor is shot, would the harness on the mj swap over?

[Geonovast]

You can keep your current wiring, they're both Renix 2.5s.

 

If you're not concerned about having 4wd, you won't even need to touch the axles.  If you do, however, you'll need to match the gearing.  Swapping both over from the XJ is going to be your best bet all around.  It'll get you 4.10s(you don't want 3.55 if you plan on using that 5th gear), and it'll keep you from tracking down a new front axle.

 

And yes, the XJ wheel base is much shorter than either of the MJ wheelbases.   The XJ shaft will be much too short.

[Eagle]

its a 4 spd manual right now. so i would have to do both front and rear axle swaps? i assume since i would have to have the drive shaft shortened the two wheelbases are different? Also the wiring harness around the battery of the donor is shot, would the harness on the mj swap over?

 

The AX-4 4-speed and the AX-5 5-speed are the same transmission. The 5-speed just has some extra internal parts to run the overdrive gearset. I'm not certain, but the long tailshaft on the 2WD 4-speed might be the same length as the transfer case on the 4WD, which would allow you to use the same rear driveshaft.

 

Yes, you have to do something to make the ratio in the rear axle match the front. The 2.5 liter 5-speed had 4.10 gears. Your 2WD 4-speed has a 3.54 rear axle.

[Geonovast]

The 2wd tailshaft is not even close to that long, unfortunately.  That would be nice, though.

 

When I did my first 4wd swap(2wd AX-4 to 4wd AX-5/NP 207), I had the driveshaft cut down by 11 inches.