np231 interchange

[jeepcoma]

I've been looking for a spare AX-15 and NP231 to have on hand and swap into my '91 HO. I know some of the cases are clocked differently, but I don't recall any details. I found a NP231 from a '99 Cherokee, and it has a slip yoke eliminator. Is this any good, and is it a direct swap? What's the point of a SYE, any benefits for non-offroading? Normally I'd search on my own but I'm at work and only have a few minutes to waste so thanks in advance :cheers:

 

Is there a "best" year AX-15/NP231 (or NP242) combo that's a direct swap without having to hammer the tunnel or change splines or anything?

[jimmy21669]

You can use the AX15 and 231 found behind any 4.0 HO. They will all be 23 spline, as is yours.

 

The T-cases were not clocked differently on XJ's and MJ's. The YJ's were clocked up, and it is the tranny output housing that is clocked, not the t-case.

 

The SYE is for eliminating driveline vibrations due to high system angles, allowing the use of a double cardan shaft in the rear. This would require you to have a rear driveshaft made. Not worth the additional cost for a street machine.

 

 

Hope this helps.

[mjeff87]

not to offend, but are you sure that TC has an actual SYE installed, or is it just the newer style case with a (stock) sealed output? If it does indeed have an SYE you'll have to build or have made a new rear driveshaft. If it's just a sealed output you can reuse your existing shaft.

 

Jeff