The axle in the XJ used a Dana 30 that is exactly (if im not mistaken) like the one in my 96 ZJ limited, only it has a vacuum operated disconnect on the axle shaft that engages when you put the truck into 4x4, making it a 3 wheel drive with the open rear diff. my 96 Grand has a plain open dana 30 in the front and i have a powertrax no-slip in my dana 35. i was thinking i could swap in the diff from the xj, and convert the vacuum system to a cable engagement system to have a locked front axle.
Hope that clears it up
The Xj's have coilspring front ends, and so do some of the newer YJ's. i think the spring hangers and mounts are all the same,
part numbers for the axle housings are the same as are most of the parts except for the differance in the disconnect!!