Hello. I am new to the site and really need some help. My son was driving the truck and started hearing some pops out of the rear end so he called and I went and picked it up. When you shift into drive the rear wheels seem to be partially locked up, causing the tires to chirp in drive or reverse. There is a loud popping noise and then it drives like nothing is wrong. But if you have to slow and then accelerate, sometimes the tranny sounds like it is disengaged, the RPM's shoot up and after you take your foot off the gas it engages again. The truck has 155K miles on it. I can work on the front end of the truck but have no idea about the rear end. Some folks have told me I should change the clutch pack??? I haven't opened up the rear end yet, I wias planning on doing that today but I'm not sure what to look for.
Any help would be appreciated.

 

Check your rpo codes in your glove box and see if you've got a g80 code. Those diffs have a mechanical locker and are prone to failure. With what you're describing I'd lean to a failure there.

Good luck!