Audi A6 C7 Quattro - Torsen fluid

[Lotobear]

I mistakenly, in a moment of madness, dropped the fluid from the torsen diff on my A6 Allroad C7 3.0TDI rather than the engine oil. What's done is done. Managed to strain it and get 95% of it back in so at least I can drive.

However I will now do a proper fluid change as soon as possible - does anyone know the correct fluid to use, I think it needs round 3lts?

Cheers for any pointers.

[normalbloke]

Tried Opie oils?

[Lotobear]

Yeah tried opie but they don’t show it

[Lotobear]

I've managed to find out that its a 75W90 but with a small amount of 'Sturaco' friction modifier added - though some forums say the Sturaco is only required in a new diff and not as part of a fluid change after the diff has bedded in.

I've pinged Opie a message asking what they recommend as non of the fluids on their site mention meeting Audi spec or that they are for use in a torsen diff.

[Lotobear]

Found it and ordered 3 litres:

https://www.ravenol-direct.uk/ravenol-awd-tor-flui...

[Lotobear]

Should have ordered 5 litres, just discovered it takes 4.35

...so that'll be £150 - just to buy the oil to fill the transfer box/torsen!