oldguy52

Got the Advanced Adapters SYE and my original plan was to modify spare tcase from 89 that I had to minimize down time. However, when I broke down the 89 tcase I discoverd blown chain (no surprise) but what was a surprise is the case had been damaged and repaired with metalpoxy from a prior blown chain. Not a good candidate so I pulled the running 94 tcase from my ride and dissasembled.
After having the needle bearings pressed out as required and starting the assembly I noticed that I had no brass synchro ring for the 94 tcase. Thinking I misplaced or dropped on the floor I exhausted all possibilities and the I noticed the following. The drive gear on the 89 had a polished surface where the brass synchro ring would sit and the 94 did not. Moreover, if I put the brass syncho on the 94 it does not sit all the way down and would prevent proper assembly. All the parts lists I've googled indicate its the same synchro 89-96 but make no indication of the synchro being optional. My take is there was no brass synchro either from factory or prior assembly. Pic below of assembly with 94 on the left and 89 on the right. I'm considering using the 89 syncro assembly thinking this was a factory cost saving maneuver. Ideas/Opinions?

oldguy52

Continued searching and found what I was looking for on Jeep Forum and similar explanation on an Arizona site.

The syncro stop ring was only needed on XJ, YJ with CAD to support "Shift on the Fly". All others with solid axles didn't need it as the front drive shat would already be spinning in sync with the rear and shift on the fly would work without it.

There will be exceptions where syncro tcases ended up in non-CAD Jeeps during conversion years but 94 XJ clearly didn't have it and I'll proceed without it.