Transmission fluid

[Charles H Jacobus]

I haven't changed my transmission fluid yet since I bought the car a couple months ago. I'm thinking of using Mobile 1 75W140. Have you guys used this? Any thoughts?

ChuckJ

[Jules Dielen]

Swepco 201

[Paul Lima]

I second Jules recommendation. Swepco 201 85W-90 will make you think you've just had a great rebuild. Also, if you choose not to use Swepco don't go to a wide temp range like 75W140. I'd recommend sticking with 90 weight.

[Doug McDonnell]

viewtopic.php?f=1&t=40632&hilit=gear+oil&start=0 While I use Swepco in my rebuilt by Vic transmission I would use a good brand name gear oil as Vic recommends in this link or you may have more leaks than you like.

[M Penta]

Per Vic (who's opinion I highly value!) I am using a regular dino 80w90 Valvoline and plan to change it frequently, but like you I was thinking of trying the 75W140 synthetic next time around. Last time I did research on oils it made my head spin, but most seem to go with the swepco. I want to put the best oil there is in my precious trans, but I am not sure what it is? So far no leaks at all so I am comfortable trying synthetic...

One thing that makes me a little wary of using synthetic gear oil in a transmission designed before such oil existed, is when I blew up a Quattro transmission, due to pin coming out of center diff. Same thing happened to another Audi I know of with same transmission. We both were using Redline, while manual recommended 80W90 non synthetic. Probably just a coincidence, both cars were used very hard at hill climb events.