Hello, CF Folks!

Been a while since I posted. Question for the transfer case gurus. Current setup in my 91 XJ is 4.0/AW4/NP231. I have always wanted the NP242 for the FT 4x4 option. Shocker, not far from us, someone is selling a 242 for a good price.

Problem is this setup is from a 1989 XJ. Still the 4.0/AW4. My research says I have two things to be wary of: spline count difference and bearing size for the input shaft. Also the older t-case will be gear driven speedo while mine is electrical.

I know the 231 and 242 share a few parts. Would this be as simple as swapping input shafts and replacing speed sensors? Not sure if the main shafts are similar enough to just put my 23 spline 231 input on in place of the stock 21 spline one. Appreciate any and all help!

 

bump

 

Yes, you can just swap the speedo sensors. You might be able to swap the input shafts to resolve the different spline count, but you'll need to confirm they have the same gear cut and bearing width. https://www.novak-adapt.com/knowledg...g-input-gears/

Also if you have the front axle disconnect, you'll want to rig that to be always engaged.