ls1ws6kid

I have to do pinion bearings in my car and i have heard by a few people that
Synthetic diff fluid is not ideal because it holds more heat then normall diff fluid?
Any imput would be appreciated..

jsteele90

iTrader: (13)

for the rear just get what gm recommends. personally I wouldn't spend the extra money on synthetic for a rearend that is going to break anyway. make sure you get the friction modifier from gm also

2QWK4RU 06 GOAT

iTrader: (1)

Just about every late model vehicle out there uses some kind of synthetic. I rebuild many diffs and all of my builds require a good synthetic for one reason or another. I have never had anyone come back due to a failure of running synthetic fluid.

Conventional fluids are fine when diffs aren't run past their heat capacity and/or the lsd is asking for it.

RPM WS6

iTrader: (3)

What year is the car?

'99+ car with Torsen rear, the factory fill was 75w90 sythetic to begin with.

'98 car with Auburn rear, the factory fill was 80w90 conventional plus LSD additive.

demonspeed

iTrader: (7)

This. I've exhausted searching through threads recently to determine what I'd replace mine with. If 99+, you don't need the friction modifier when using most synthetics as it already has it in there.

2QWK4RU 06 GOAT

iTrader: (1)

Fm isn't really needed on a torsen. I would use it in a new build, it keeps temps down during break in. Redline ns gear oil has no fm. I'd still add an ounce or two max for a cooler running diff.

mjs1012

iTrader: (36)

In my 98 with an auburn I use cheap 80w90 w/ a bottle of LSD additive.