Thump...

[Palazzoblues]

Okay, so here's the deal... I just purchased a brand new 2016 Chevy Silverado 1500 High Country crew cab short bed 4X4 5.3 8speed (Not Z-71). I have already noticed a weird issue and want to know if this is normal or something I should take it back in for. What it's doing is a pretty strong thump-bump somewhere in the rear end when I make a slow left hand turn with little or no gas. Basically if I am in a slow rolling turn to the left the rear end makes this somewhat violent THUMP! I don't think it is transmission related. I think this is more transfer case or even rear end differential related. This pickup does have the auto-locking rear end diff. I wonder if it has anything to do with that? Also, this seems to be an intermittent issue. Thoughts?