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View Full Version : Fitting an 90' AX-5 to a 87' 2wd Comanche


JPWilson
September 20th, 2006, 14:06
This is a question for my little brother who just picked up a cherry 87' 2wd Comanche Sport Truck (2.5L, 4-spd) with 43K from the original owner. He's looking for a pretty much bolt-on conversion to make his truck 4wd.

I recently found an 4wd AX-5 (complete w/bellhousing), w/10K from a 1990 YJ for $300. Would this bolt right up to his 2.5L? And will the current transmission crossmember work without modification?

I have searched, but I haven't got a direct answer, so I might not have searched hard enough :dunce:

I heard that they changed the slave cylinder(?) sometime in the 90's so I just wanted to make sure with NAXJA :worship: that this would work with his current set-up. Any tips on the conversion would be great too. Thanks in advance!!!

CanMan
September 20th, 2006, 16:48
The crossmember may need to be changed out. The trans should bolt up to the 2.5L. Use the same hydrulics as in the truck, but new. HTH.

JPWilson
September 20th, 2006, 21:34
Ok, since the trans SHOULD bolt up, I'm assuming the crossmember will need to be moved back a few inches? Anyone have any specs on the length of the AX-5 vs. the 4 spd.? Any other suggestions on what transmission I should look for. The main thing I was worried about was the hydraulics not being the same.

87manche
September 21st, 2006, 06:32
ax-4 and ax-5 were practically the same trans. It will bolt right up, I know because I helped a guy do it.
The bigger question will be the t-case clocking. I know that yj AX-15's have the case clocked higher, you may have to clearance the floorpan a bit to fit it. On the other hand, the case won't hang low ;)

RichP
September 21st, 2006, 07:18
ax-4 and ax-5 were practically the same trans. It will bolt right up, I know because I helped a guy do it.
The bigger question will be the t-case clocking. I know that yj AX-15's have the case clocked higher, you may have to clearance the floorpan a bit to fit it. On the other hand, the case won't hang low ;)

Yea, the clocking was an issue, my sons friend is going thru that now, I think he solved the problem with a 5lb sledge and some massaging of the floor pan... He's converting a 2wd XJ to 4wd using TJ parts...

Jeff in VA
September 21st, 2006, 08:12
Trans will bolt up directly, and the Xmember will work. The holes for the TC will be clocked about 10% from an XJ/MJ trans, so the TC will sit higher (closer to the floorboard)...you may have to clearance it a bit with a heavy blunt object of your choice. Internal/external slave won't have any affect, the hydraulic line is the same, as well as the master cylinder. Just plug it all up and bleed it and you're good to go.

Try to get the matching TC along with the tranny if you can, because I ran into a problem converting my MJ using a YJ tranny. The output end of the tranny can either be flush or recessed, and you'll need the correct TC with corresponding input shaft length to make it all work together (you can use a long input in place of a short one, but not vica-versa....not enough spline engagement and it will leak at the seal). I ended up pulling the YJ tranny back out and replacing it with an XJ one because I couldn't find a 21 spline TC with a long input....it wasn't fun.

PM me if you have any other conversion questions. It's not a hard job, but there are a few things to watch out for (like above). Here's a pic of the difference in the outputs between the two: (YJ on left, XJ (currently in my MJ) on right
Jeff

http://img.photobucket.com/albums/v220/mjeff87/sidebyside-1.jpg

JPWilson
September 21st, 2006, 12:45
Thanks for the input, I'll probably be PMing you with more questions once I round up a t-case.

JPWilson
September 21st, 2006, 15:11
Ok, I got a few lines on t-cases. I should be looking for 21 spline t-cases, not 23-spline right?

Jeff in VA
September 22nd, 2006, 04:42
yep, 21 spline

Jeff