Rear Differential Fluid Replacement Schedule
Race Director
Joined: Sep 2007
Posts: 16,557
Likes: 2,108
From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
To the OP: When GM has no set service intervals, the assumption is either service as needed or at the 150K mile expected vehicle life.
Team Owner
Joined: Sep 2000
Posts: 25,019
Likes: 2,712
From: Far NW 'burbs of Chicago
St. Jude Donor '13
Nothing in the book, and 3 yrs/30k miles sounds like a ripoff unless something is getting noisy.
I had the dealer change my diff fluid at about 7k just to get the manufacturing crud out, and plan to do it again at 50k. But if the dealer told me to do it, I'd be saying WTF...
I had the dealer change my diff fluid at about 7k just to get the manufacturing crud out, and plan to do it again at 50k. But if the dealer told me to do it, I'd be saying WTF...
I had it changed again at 50k miles and sent a sample to Blackstone Labs. They said the fluid and the diff itself were in excellent condition, recommended going longer on the next cycle.
But perhaps my early change at 7k helped the situation.
