Hello,

I am changing my 6spd transmission and differential oil. I see some people are using the Shell Spirax 75W90 synthetic gear oil in transmission and differential oil. This oil is rated GL-5 which isn't compatible with the 6spd transmission (GL-4 needed). However, there has been some talk that the Shell gear oil is copper friendly. To those who are using this product, how does the transmission feel compared to the OEM fluid? Is this safe for our transmission? How many miles have you put with this fluid?

Also, do all G35's have LSDs in the differential? Is any friction additive needed?

I would like to hear your opinions. Thanks.

 

+ 1