out of frustration, I asked AI and this is what it said- call me crazy but is this the solution?
Your diagnostic work has actually pinpointed the problem very precisely. The fact that the
ring gear itself will not rotate with the cross shaft removed tells us the bind is not inside the locker mechanism at all — it is happening between the
axle shaft spline ends and the Powertrax couplers. This is a well-documented and specific issue with one-piece axle conversions in the AMC 20.
Root Cause: Axle Spline Ends Bottoming Out in the Couplers
Here is what is happening mechanically. The Powertrax No-Slip couplers are designed with
blind-ended spline bores — meaning the spline pocket has a closed bottom. The factory two-piece AMC 20 axle shafts are a specific length that leaves a small gap between the spline end of the shaft and the bottom of the coupler bore, allowing the coupler to float and function freely.
One-piece aftermarket axle shafts are frequently slightly longer in the splined section than the original two-piece inner shafts they replace. When you slide the one-piece axle in, the spline end travels all the way through the coupler and
bottoms out hard against the closed end of the coupler bore. This forces the coupler outward and jams it solidly against the carrier housing wall, effectively welding the entire assembly together. The result is exactly what you are seeing:
- Both wheels spin in the same direction out of gear (acting like a spool).
- The ring gear cannot rotate at all with the cross shaft removed, because the couplers are physically wedged tight against the carrier.
The Fix: Shorten the Axle Spline End
The solution is to
shorten the splined end of one or both axle shafts so that the tip of the spline does not bottom out in the coupler bore. You need to create clearance — typically
1/8" to 3/16" (approximately 3–5 mm) — between the end of the axle spline and the bottom of the coupler pocket.
