Rear End Squeal/Chirp Axial End play?

[Kevin Ryder]

Hello, anyone with knowledge on a 2010 Sierra 1500 SLE Z71 5.3, the rear end , please reply, I got a nasty squeal combined with a chirping, coming from the driver's side rear, a little less on the pass. side, figured brakes were shot, replaced everything drums on down, and it's still there,  my question is how do I decrease end play, would it be a worn center pin in the pumpkin? I mean the axles not falling out, but just a twitch of the steering wheel to the left and the noise goes away momentarily,  any help appreciated,  Kevin R.