Well for the last couple of days I have been hearing a groan in the rear end when turning left or right. Sounds like a out of round tire scuffing the inner fender well... womp womp womp. I know its coming from the rear diff.
I took it in to the dealer and they called me back and said they have a TSB on this and it requires a rear diff flush, and addiing some additives.
Is there really a TSB or are they putting a band aid on a failing rear diff?
History of diff......
Had leaking rear diff at 6k and had dealrer replace rear seal with factory seal( I would assume you would drain the fluid and replace with new at this point)
At 28k had dealer replace rear diff seal with the new GM corrected rear seal. ( again I would assume a fluid change at this point again)
at 32k groan appears in the rear diff.