Rear Diff Lube Question
Thread Starter
Team Owner
Joined: Jul 2004
Posts: 28,422
Likes: 3,273
From: Hartford WI
Rear Diff Lube Question
According to the Tech Tip it said that we should use 75w-140 or 75w-90 weight, with 75w-140 being the preferred weight. My GM service manual said that we use 80W90. So, what will it be? 75W90, 75W140 or 80W90? Why is 75W140 the prefered weight?
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
hm. news to me... I would use the GM recommended, or, the closest you can get.
One thing I have learned, if the oil is too thick, then the oil might not get where it must.
Oh, Gordon Killebrew recommends two bottles of GM diff additive.
One thing I have learned, if the oil is too thick, then the oil might not get where it must.
Oh, Gordon Killebrew recommends two bottles of GM diff additive.
t for get the whale oil!
Safety Car
Joined: May 2002
Posts: 4,010
Likes: 26
From: Somewhere nowhere
I would like to see the documention from Dana. GM calls for a very specific gear oil for each vehicle. If you search through GM's gear oil selection, they have many many many different part #'s just for gear oil.
