Rear Diffrential leak

[mike66]

Mine is a 2008 GMC 5.3 seirra, with 120000 Kms, (still under power train) , recently I changed both diff and T/box oil at a licienced shop in calgary, noticed now, a month and about 1000 kms later that the rear diff is leaking from the cover joint , to replace oil in rear diff the cover was removed. Want an opinion, should I go to the same guys to have this checked or should I go to the dealer or a tranny shop to have this checked? Jutst a little suspicious of this shop as they had also put AutoTrac fluid into my T/box instead of Dexron VI which I made them replace again. Worried just in case the rear diff is damaged due to low oil level or over tightining the rear cover . Appreciate an opinion , should I go to the same guys to have it fixed or check it out with another shop.

[tanked_darren]

I doubt you have much in the way of damage if its a small leak. The question is what did they use to seal the diff. If they are licensed they should come through on the leak. This is a complicated situation if you go to a dealer. Either way start with having the "shop" fix their mess up and if a failure happens after that don't tell the dealer about your situation, you are allowed to use other services to do maintenance. This is why im so particular about the little work I allow shops to do instead of myself.

[tanked_darren]

Another sure way to protect yourself is to have the dealer service your truck right before warranty end, if there is damage they should fix it, they can't deny you because you went somewhere else in between. They might try, but they can't.

 

You'll be screwed if they aren't using correct fluid in the diff though.