'91 Audi Coupe 7A Manual Transmission and Rear Gear Oil

[cgharibo]

The manual transmission hooked up to 7A has 310,000 miles. The fluid has only been changed once at about 120,000 miles. There are no leaks.

Do I need to change the MTF and gear oil? Actually, never mind! I want to change the MTF and rear axle oil.

I used Audi oil long ago that is no longer available. I remember using Redline and shifting was noticeably poor in cold weather. I changed back to Audi oil (G50?) and shifting improved greatly.

What should I use this time around. I live in a 4 season environment and can drop as low as -10 Fahrenheit.

I see below listed:

Moly 75W90 Fully Synthetic Hypoid Gear Oil
Motul Gear 300 LS 75W90 (1 Liter) - Motul 105778
Audi VW Gear Oil Synthetic 75W90 - Genuine VW Audi G052145S2
Mobil 1 104361 75W-90 Synthetic Gear Lube

Thank you!

[Tractor Dave]

Can you get Castrol syntrax 75/90? Very good stuff. Just don't use a GL5 in your gearbox due to sulphur and brass synchro. Rear diff EP90 gl5 of high quality.