I have a 2004 2500HD 4x4. I am having some binding in the rear axle when making slow sharp turns. The inside wheel wants to turn as fast as the out side wheel. An oil change mechanic told me that when my trucks in 4wd the rear axle locks and becomes a positive traction axle. This happens even when I haven't had it in 4wd. Can anyone help me?

 

The g80's have a tendency to blow up, if you have that diff it might be going south on you.

 

posi works whether its in 4 or not there is no input from the driver unless its an aftermarket setup. Have you had the fluid changed recently? It could be as simple as not having the right fluid or additive.