I just bought a 07 Silverado Classic 1500 with the 4.8L. It did not come with an owners manual, so I am wondering what fluid is best for the rear differential? I called Chevy and the guy (who seemed clueless) said AutoTrak II. But the Haynes Repair says SAE 75w90 synthetic gear oil. What is the best to use and how often do I need to change it???

I do not tow, but have a camper in the bed and drive on long trips out of state atleast once a month.

 

Sign in /up here and you can access your owners manual online, download it. go with what Chevy recommends not the Haynes manual
http://gmownercenter.yahoo.com/portal/landingpage.php

 

FYI,I Just had all my fluids done.The Auto Trak 2 is for the transfer case only. You must use it if you have the dash push button 4x4 system. BTW, you can only get it at the dealer.

 

i use royal purple 75w90 full synthetic in the rear end.

 

chilton manual says to change it every 6k.

 

I am changing all the fluids on my 2007 chevy 4x4 new body style and I was just wondering what to put in the front differential, rear differential, transmission, and transfer case?