OK. Moving wheels from the parts XJ (87) to the 90 XJ. It seems there is a difference in stud length. The studs on the 87 are longer than the ones on the 90. So there is a concern over thread engagement. Yes, the 90 has steel wheels, the 87 has alloys.

Is there a real rational reason for this? would we be SAFE in putting these factory alloy wheels on the 90?

 

The alloy rims, I'd say, are definitely the reason for the longer wheel studs on that rig. You can run the alloy rims on the 90 XJ just so long as the studs are long enough to get a lug nut about 6-8 turns on on them.

 

Thats just silly (from the factory). If the 90 hadn't already had some parts thrown at the axles, and the 87 axles weren't 3.07s, I'd just swap axles too. I'll check thread engagement when I get home. My son (20) was doing the swap and is concerned. The 90 is my daughter's XJ.