Recommended Fluid For Front/Rear Diffs On 99' Tahoe
02-26-2010, 09:53 PM
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Recommended Fluid For Front/Rear Diffs On 99' Tahoe
Got all fired up to change front/rear diffs and transfer case on my truck. Went to the dealer to get the auto trac II fluid for the transfer case and started talking to the counter guy about the diff oil.
So I looked in the manual and it lists a GM part number and says ONLY use GM part number......80-90wt and add no friction modifiers. This is for the rear diff which has the G80 locker.
SOOOO, my question is do I have to buy that special GM oil at $18/quart (need to buy 3) or can I buy Valvoline 80-90 and be done with it. A
Also, every limited slip type rear end I've had I've always put a limited slip additive in when I've changed out the fluid but the manual says, "add no friction modifiers" for the rear.
Any input would be greatly appreciated. (truck is a 99')
So I looked in the manual and it lists a GM part number and says ONLY use GM part number......80-90wt and add no friction modifiers. This is for the rear diff which has the G80 locker.
SOOOO, my question is do I have to buy that special GM oil at $18/quart (need to buy 3) or can I buy Valvoline 80-90 and be done with it. A
Also, every limited slip type rear end I've had I've always put a limited slip additive in when I've changed out the fluid but the manual says, "add no friction modifiers" for the rear.
Any input would be greatly appreciated. (truck is a 99')
02-27-2010, 11:01 PM
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