hello everyone, i did a search on this and couldn't find anything conclusive, so i decided to post this. my car is a 2000 c5 a6 4.2 quattro tip and just recently i've started hearing a noise from the front of the car, a sort of gear whine type noise, and only on deceleration. i know it's not the timing chains because the car won't do it if i pop it into nuetral when i'm slowing down instead of just keeping it in drive. it only started doing this too just a few days ago. mostly it only made the noise when the driveline was still cold, but after it warmed up, the noise went away. unfortunately that wasn't the case today when i drove home, because it didn't quit at all. does anyone have any idea what the problem could be? thanks in advance.
-mike

 

also, from what i can tell, there's no visible leaks anywhere that i can see. the only thing i can think of that might be creating the noise would be the transfer case, or front diferential maybe, since these cars don't have transfer cases, do they? could it maybe just need a fluid change or something? i'm also not throwing codes or anything, and it drives perfectly fine, it's just making that annoying whining noise when i slow down.

 

over 20 hits and no replies? does anyone have any ideas?

 

It could be something to do with the valve body in the trans or the tcc locking up ect. I recommend replacing the fluid and filter in the trans then driving it again.
If there are no faults it should be ok but when you drain the fluid check for any metal debris in the fluid just in case.

 

ok, i'll try that. anything in particular you need to know in order to replace the fluid and filter? also, one other thing i noticed today. the car won't upshift when in tiptronic mode any more. it'll downshift, but not upshift. when i leave it in drive though it drives fine. and idea what that could be? i'm assuming it's related, i don't know though. could always just be the stupid magnet in there i guess, just seems like a pretty big coincedence.

 

You need to fill the transmission from the bottom of the car which is difficult without the special tool, and it has to be running. The trans temp has to be about 35 degrees celcius to know if its full or not, i suggest
on having it done by the dealer.
As for the tiptronic problem its probably not related, more like the magnet under the shifter assembly like you were saying.

 

well i think i'm gona go ahead and attempt it by myself since i have two car lifts. i read up on a couple of different people (on stoney's link site if i remember correctly) that have done it themselves and are very knowledgeable in that area, and the process seems pretty straight forward to me. it does help that i've also got Vag com, so i can monitor the transmission fluid temperature to get the level right. i figure that i spent over $200 on the software and cable, so i may as well make some use out of it, and this way i'll be saving myself several hundred dollars easily by not having a shop do it for me. as for the tip magnet, i guess i'll just have to pull the shifter cover off and take a look. anyways, thanks for the replies auditech79, i'll post an update after i change the fluid and filter on whether it's still making noise or not so that maybe someone else with the same problem may get some use out of this thread.

 

ok, i just got off the phone with the audi dealership here, and the tech told me that my problem might be with some sort of shaft, but i forget exactly what he called it. he doesn't think that it has anything to do with the transmission since it's still shifting perfectly fine and i haven't had any problems with hard shifting. anyone ever have this same problem that i've described? i'm just trying to figure out exactly what shaft he was talking about, wish i could remember. guess i might have to try and call him back again.
thanks,
mike

 

Its really hard to diagnose a noise without being able to hear it, he was probably talking about the half shafts or output shaft. But hey it could be anything, your driveline, front axles, torson diff, rear diff, there are tons of things. If you have access to a lift, have someone take it up to speed while on the rack and listen for the noise from below, just make sure to turn off the traction control.

 

that's a really good idea, i don't know why i didn't think to do that. i guess i'll put it on the lift and see what happens.