gear oil - center
 

what aree using these days?

Redline MTL MT-90 GL-4

While I am a fan of Redline, and they were a race car sponsor...
 

of mine years ago, I am not sure I would use it in the Audi. I put it in two of my 200s and I found that both cars developed leaks on seals and maybe gaskets of the transmission. I am not sure it was a Redline issue, but it was odd that both cars had the same issues after putting in MTL. My current car has synthetic in it, I recall it is Valvoline, and have not had issues.

It is possible that there is something in the Redline MTL that does not work well with the type of gaskets/seals used in the older Audis.

I put it in my v8 5spd several years ago and no leaks
 

It's been in my 20v Avant since well before I bought it and no leaks.

I put it in my CGT several years ago along with some Militek and no leaks.

YMMV

Can never go wrong with OE Audi oil Allen. I know a few who are experamenting
 

with Royal Purple.
But when I swapped out my oil in my 5sp I used OE Audi oil in the trans & rear diff.

I too, agree with Redline MTL MT-90 GL-4
 

on my 87 Grey, while I was installing the new clutch toys I added the Redline fluid. No problems...