The Stovebolt Site Forums The Shop Area Driveline 1951 3/4T Pinion Rebuild stiff

It's been nearly a week since the last post in this thread. If you still haven't solved the problem, here's a few more comments on oddball situations:

If all's well with the pinion assembly when out of the carrier with the yoke and nut on and at least somewhat tight, I would suspect some bearing bore mis-alignment. I have run into that where the outer race bores on a stradle-mounted pair of tapered rollers were not square with each other. This resulted in repeated bearing failures for no apparent reason. I no longer remember what tipped me off but I ended up having the case bored square and sleeved to take the outer race. This was on an expensive, heavy-duty transmission and so was worth doing.

Maybe somebody left the preload spacer out for a reason and used the castle nut to set the preload. Had one of the pinion bearings failed or did you replace all the bearings for some other reason? Maybe the bore for the pinion-nose bearing isn't concentric with the pinion bearing bore or possibly the pinion-bearing bore isn't square with the differential-bearing saddles, which will try to make the nose bearing off center with it's bore and cause a bind of the pinion bearing if it's preloaded. Try installing the pinion assembly without the nose bearing and observe if that bearing inner mount is concentric with the outer bearing bore. Also note if the pinion turns freely with the nose bearing off and if the pinion retainer now sits in position properly.