GM truck rear end help...

[Hank70SS]

Well I've had Suburbans, and pickups with both open and locking. One Sub, early 90's, 91 I think, the rear started locking up solid. The dealer cleaned it out and installed new fluid, no more problems. The 96 Z71, no problems with the rear but I can't swear what type of locking diff it was. Current 02 Z71 has an open rear. It really isn't bad, if I need traction there is always 4wd. That's all I can offer. If the truck is 4wd and you really need 4wd then an open rear, although it sounds unusual, works pretty good. I can go through 8" to 10" of snow in 4wd with no problem. Haven't had the opportunity to go through more but wouldn't be afraid to try it.

Looks like you been on the GM truck boards, lot of good info there on various problems.