Quadrasteer Diff Lubricant

[knofun]

I have an 02 sierra denali with quadrasteer and am experiencing what I now know is a fairly common problem. I had new tires put on and they must have changed the diff fluid because I soon experienced the 'moaning' sound when turning that many quadrasteer owners have reported on this very forum. I know that the answer is to replace the fluid in the diff with GM part #12378557.

 

Problem is, everywhere is sold out of it because GM discontinued the part. Have any quadrasteer owners found a suitable replacement?

[knofun]

 

According to this I can use AMSOIL Severe Gear 75W-90 as an alternative. Anyone had any experience with that?

[PhilB]

You can get a couple of bottles of the GM posi lube and put that in the diff. That should take care of the moaning sounds. The GM gear lube contains more of the posi lube than regular gear lube. When I had my QS, I would add an extra bottle of the posi lube to keep things quiet.

[jandersinc]

Why would they change your diff fluid when changing your tires? Especially if they didn't tell you or you didn't ask them to.

[SpeedyV]

Problem is, everywhere is sold out of it because GM discontinued the part. Have any quadrasteer owners found a suitable replacement?

 

When was it discontinued? I just changed mine a few months back. My closest GMC dealer didn't have any (the guy at the counter didn't even know what Quadrasteer was), but a local Chevy dealer keeps it regularly stocked. They even have bottles of it sitting on display by the parts counter.

[SpeedyV]

Maybe I should stock up for next time!

[knofun]

Turns out my local dealership had some stock, took it in there for the service. Thanks for the replies.