warp_foo

I searched and didn't find anything relevant, so I'm posting this question. Apologies if it's been done to death.

I have a 2003 S8 with a 5sp auto. After an oil change and the installation of a new stereo/nav unit, on occasion, the transmission will drop down one gear, or drop out of gear for an instant. The it resumes normal operation. The car currently has 104K miles.

Generally, it does this withing a few minutes of starting a drive, but today it did it after driving about 40 minutes, on cruise, steady at ~56mph. It immediately resumed normal operations.

I don't know if the oil change and stereo are relevant, but I'm including both to be complete.

At no time am I getting a check engine light or any change in the LCD display indicating that there is a fault.

Thanks,

Mike

warp_foo

Well, I did find this posting from 2003:

https://www.audiworld.com/forums/sho....php?t=1737486

Could this be what I am experiencing?

m

silverd2

I'm guessing it's not the same issue for a couple of reasons;

That discussion was about pre-facelift D2's (pre 2000), which are notorious for different trans problems than later models...mainly TC clutches acting erratically and abruptly...not a common problem in later trans's.

Also your description of symptoms does not sound typical of a TCC problem...dropping 1 gear or dropping "out" of gear.

Tozo may have an educated/experienced opinion when he sees this post...but one good recommendation repeated in that thread (and often overlooked) is to check the ATF level with the emergence of any trans problem. PLUS on these cars (easily doable) is to check the electronics box (in fresh air plenum under the hood...contains ECM & TCM) for water intrusion and/or corrosion at the electrical connections.
Not the only things to check, but 2 of the more obvious starting points.

warp_foo

I dropped off the car to get the trans serviced (had the diffs serviced as well...). Had the fluid and the filter swapped out.

Thus far, the problem seems to have been corrected. No fault codes in the ECM or TCM were noted. Prior to today, the trans 'blip' was consistent, so after driving the car both when warm and after a cool down period, I'm cautiously optimistic the issue has been corrected.

m