Anyone running 75W90 synthetic gear oil?

[sleepr]

I'm just curious if anyone is using 75W90 in thier differentials, I got some synthetic 75W90 from my cousin at the GM dealer and wanted to put in my axles. The rear is a standard axle(non G80). Will it hurt anything? I'm pretty sure the stock fluid is 80W90.

Thanks a lot

Blair

 

[Code187]

DIFFERENTIAL FLUID

FRONT AXLE (FOUR-WHEEL DRIVE)
SAE 80W-90 Axle Lubricant (GM Part No. U.S. 1052271, in Canada 10950849).

FRONT AXLE (ALL-WHEEL DRIVE)
SAE 75W-90 Synthetic Axle Lubricant (GM Part No. U.S. 12378261, in Canada 10953455) meeting GM Specification 9986115.

REAR AXLE
SAE 75W-90 Synthetic Axle Lubricant (GM Part No. U.S. 12378261, in Canada 10953455) meeting GM Specification 9986115.

Hope this helps.

 

[retorq]

Exactly how does a AWD and 4WD front diff differ??

 

[SunlitComet]

It provides for faster axle switching in cold climates. I suspect in all wheel drive with multiple speed sensors around it may cuase some havoc with traction and braking system when 2 differentials carry different fluid. Internally they look the same from my data. 2005 TSB updated the fluid specs too.

 

[Nickleahy23]

yup im running it in my rear with a stock g80

 

[sleepr]

So can I put 75W90 in my rear axle only? I did just change the front but I put 80W90 in, so I can leave that, but would like to change the rear to synthetic.

 

[SunlitComet]

if you have awd and not part-time option then change the front to synthetic.