am_ver

Planning to change the differential fluids with redline this time (used AMSOIL last time). For the rear differentials, there are two versions of the GL5, 75W-90. Anyone someone who has used this in the past confirm which oil should be used?


Rear: GL5 75W-90
Non-slip: https://www.fcpeuro.com/products/75w...-redline-58304

Or,

Regular:

The front and TC fluid seems pretty clear and I plan to use the below.
Front and Transfer case: RED LINE MT-90 75W90 GL-4 GEAR OIL (1 QUART)
GL-4, 75W-90 Synthetic Manual Transmission and Transaxle Gear Lube (75W-90) Buy Red Line MT-90 75W90 GL-4 Gear Oil (1 Quart) - 50304 by Red Line | Europa Parts

raj99

Hi am_ver, I used redline when I did the diff on my car and here's the thread on it: https://www.audiworld.com/forums/a6-...-oils-2843310/

I used Redline SAE 75W-90 API GL-5 for the front and rear transfer case

BTW, both the hyperlinks you embedded go to the same page.

am_ver

Thanks Raj99. I've corrected the link for the 75W-90. I've ordered the regular (non NS) and am 99% sure that is the correct one, but thought I'd check with this group!

am_ver

Called redline customer service and their recommendation is to use:

Front: GL4; MT 90

Rear: GL 4; MT 90

Transfer case: 75W-90

Terry Babb

How did this move work out? Would you recommend it and use it again?
Thanks