So the daughters XT clutch has been going south for a while and we finally ordered a replacement from RockAuto. They only list one option for an 88 XT. I get everything torn out today, open the package... and it doesn't match what I just pulled out. Check the specs and measurements. Yep, they sent what I ordered. 7-7/8" disc, 21 spline. What came out was 8-7/8" and 24 spline. Wonderful! NOT!!! Apparently someone swapped in and XT6 tranny since the rear diff is a 3.90. Everyone else shows the same listing so it can't be a miscatalogged part. Now we have to wait for the 'right' one to show up. Joy and fun! Again, NOT!!!

That's frustrating for sure. It sounds like you might have received the FWD clutch disc instead of the 4WD one. Good luck!