Kraton Grinding gears

[jeff37311]

Ok so my truck sounds like the gears are striping I took the diff out and put 2 shims on each side but that don't seem to be helping any and I don't think I'll be able to add any more for there isn't any room.
All the gears look to be in good shape so I'm just lost in what to do.
And to top that my fireteam is starting to do the same thing, please help me figure this poop out

 

[Vulthraxis]

Did you take them apart and look at the internal gears of the diff I have had to replace a few sets eat up the internal gears no just the ring and pinion.

 

[jeff37311]

Did you take them apart and look at the internal gears of the diff I have had to replace a few sets eat up the internal gears no just the ring and pinion.

Yeah this one is brand new