mattsimis

I just picked up a 1998 Audi S8 (UK spec) with 165k miles and no service for an absolute steal (for obvious reasons!). Bunch of issues with it, one of which is the transmissions, when coasting to a stop, if you completely let off the Accelerator it will bang (thump?) physically (unpleasant) and loudly. There is no shifting problems and no hunting that I can see. The car was remapped but no idea by who or how well.

I did run a VagCom on it initially (will rerun tomorrow) and it gave a puzzling "Gear Ratios incorrect" type DTC?

Now I have read about transmission problems here, is this the issue fixed by the modded (Tozo) Valve body and if so, can someone expand on this (user serviceable etc)?

mattsimis

:sound of tumbleweed:

Since posting I note it cuts out or goes to Limp mode nearly exclusively on hill starts and stops... insufficent ATF fluid?

tozoM8

I've sent you a message.

mattsimis

So got the Fluid and filter from Audi on Friday and spent the weekend changing the fluid..

Draining the fluid.. about 6-7 litres is meant to come out.. just 2.5litres came out of mine.
I put in about 9litres .

Results:

* Limp mode and cutting out on hills appears to be completely eliminated.
* Smoother, quieter gear changes
* Thumping/slamming (caused by worn Clutch pack I guess) reduced and effect lessened. Possible to feather the throttle when coming to a stop to nearly eliminate it.


I dunno how so little fluid was in it. Im thinking someone (looking at professional mechanics here) changed the fluid before and did it the "normal" Auto trans way, treating the fill hole as a dipstick and filled just the pan without cycling through the gears (it sucks in fluid as you do that) and left it grossly under filled.