After backing up under hard acceleration and then going fwd the same way, the left rear wheel locked up and started chirping whenever I turned either left or right. It locked up much like a posi rear end would going around turns. I backed up a few feet thinking maybe that would correct whatever was going on then pulled fwd again and was still doing the same thing. After a few feet there was a loud metallic bang and after checking everything seemed normal again. I made it home without any further issues.

I drained and removed the diff cover expecting to find spider gears or metal in the casing but found absolutely nothing but clean 90 weight gear oil. Just wondering anyone out here has any suggestions as to what I should do next? This truck has 219k on it and pulls a 4700lb boat and trailer all summer long. Never had any other problems like this and don't know where or what to do at this point? Any ideas?

 

It sounds like your problem may be the self adjusting emergency brake shoes, within the rear brakes. The self adjusters work in reverse. You noted that you backed up quickly and this may have adjusted the brake shoe within the rotor to drag a bit.

If this is the problem, it is a much easier repair that the rear end.

 

Sounds like the mechanical lockup mechanism in the diff got stuck. It's pretty loud when it activates but I've never had mine get stuck locked like that.

 

Just not sure about that loud metal bang when whatever was stuck let loose? I pulled the left rear rotor off looked for something out of place and didn't find anything.

I decided to just fill it back up and run it, see what happens. If it breaks or sounds strange I'll start looking at getting it to a rear diff shop?

 

To me its most likely your locker, If I attempt a hill off camber mine locks up, chirps until I drive a bit. The bang is the locker letting releasing.

 

Thanks for chiming in, how long has yours done this, it was the first time for my Tahoe? I had planned on a lot of work this winter while it wasn't pulling a boat but I hadn't planned on anything with the rear, maybe my plans need to change some? Should I have this looked at or just let it ride?

 

Since new, Its something with the G80 locker combo. Not sure if there is cure. My 85IROC had the locker too but never acted up. However it never really worked that well either.


Not sure what to do as it is a mechanical locker.