Drivetrain Install Problems

[ComancheJon]

Alright, so I recently got my hands on an 86 comanche long bed. It had the 2.8 with the auto and 4wd in it. The guy pulled the whole drivetrain to swap in a 92 cherokee 4.0, aw4, and np242. I just ran across a huge problem and don't know how to get around it.

 

The engine seems to be sitting completely correct, yet the transmission/trans mount do not line up with each other. There is set mounting places for the crossmember, as you guys probably know. I posted on cherokee forum already, but I thought I should post here as well.

 

We tried using whatever the crossmember it is that he gave me, and the 93 crossmember from my cherokee. I am using a trans mount for a 92 comanche with the 4.0, auto, and 4wd.

[onlyinajeep726]

The '86 XJs and MJs were never designed to fit a 4.0L.  The firewall where the transmission tunnel starts sits lower than the '87 and newer models.  You basically have to modify a lot of the Jeep to make it fit right.  There's tons of information about a 4.0L swap into the '86 and older XJs and MJs on this forum and a few others.  It can be done, and eventually I'm going to do so on mine.  But it's not a direct swap...

 

Here's the thread I started:

 

http://comancheclub.com/topic/38356-40-into-an-86/

 

And here's a comparison of the firewall/transmission tunnels.  This will also address your crossmember question.

 

http://comancheclub.com/topic/31039-big-swap-help/?p=314518

[ComancheJon]

So it depends upon the application when it comes to firewall modification but the crossmember absolutely has to be moved back? That's what I'm getting from multiple people's answers