My truck is a 2000 Blazer ZR2. Automatic transmission and about 101,000 on the odometer. I just finished replacing all the seals in the rear end and made the mistake of over tighting the pinion nut to the point where the yoke was difficult to turn by hand. I removed the nut and pulled the yoke back off. I then reinstalled the yoke and slowly torqued the nut so the pinion had a rotational force of 25in./lbs. First question, is 25in./lbs even the correct number? I realize now that I should have checked this first before removing the yoke. I filled the diff with a good synthectic oil and then took the truck for a ride and right away felt a humming under the truck and heard a few unpleasant sounds when I let off the gas. Turned it around in a neighbors driveway and coasted it back into my garage. Now my next question. If the collapsible spacer needs to be replaced, can this be accomplished without having to reset the gear specs (backlash, pinion depth)? I've never rebuilt an axle before. Thanks for any input.

 

It is very possible that the crush sleeve has now been crushed too far. It is also possible that you have damaged the bearings. You should be able to replace the crush sleeve from outside, but I do not know how you would set the proper tension on the pinion gear without removing the differential. You may be able to just pop the center section out of the axle and do it that way, just make sure to keep track of all of the shims side to side so that you can put it back in the exact same orientation.

 

To gain access to the crush sleeve from outside, I would remove the yoke, pinion seal and then the top bearing? You are saying that to properly set the pinion bearing tension that the differential is not supposed to be in place? Do you know what the proper preload is? Thanks.

 

Here ya go:
Rear Differential Help