4th Sep 2007, 10:52

I own a 1999 Audi A8. The car drove exceptionally well until it hit 97k and the transmission died. I replaced it with a rebuilt transmission from a re-manufacturing company in Arizona. I used an independent mechanic to install it. Total cost; about $3500, after I returned the core. The transmission started to exhibit a nervous shift pattern between 20 and 30 mph after warming up. Two independent garages could not diagnose the problem. A local Audi dealer charged me $100 to tell me the serial number had been removed from the re-manufactured transmission and they could not diagnose the problem. They told me there were multiple types of Auto transmissions for these cars, and without the serial number there was no way of fixing the problem. So now I'm really stuck. The manufacturer in Arizona didn't return my calls, the independent installer will not take responsibility and Audi can't replace the transmission because they don't know which transmission to use. I'm still having a hard time believing there were different automatic transmissions for such a limited production car. I would really like to fix it, but any attempt with Audi to cross reference the VIN number with the appropriate transmission information has been futile.

16th Sep 2007, 00:23

I had a 1997 Audi A8 and the transmission went out at 54,000 miles. Although it was no longer under warranty the factory provided a replacement (I had to pay $1000 for installation) at no cost. Since then I have learned from several mechanics that the A8 series 1997-2003 is PLAGUED with transmission problems. I have since sold my 97 A8 and am currently driving a 2002 S8. I have just turned 100,000 miles and the transmission is starting to slip. Here we go!!!

23rd Oct 2007, 17:05

I have read the various issues re: Audi A8 transmission problems and I have one to add to the list.

I own a 1997 A8 with @ 77,000 miles. The car is a gem to drive. Recently, @ 60 MPH and higher, when I take my foot off the accelerator, the RPM drops to @ 1100, then back up to @ 1800, down, and back up again. Usually it is 2X-3X before stabilizing. This does not occur at lower speeds. The other issue is coming to a stop sign or traffic light, it now has a hard downshift @ 3-5 MPH. The Audi dealer servicing the car took a test drive with me and indicated that a new or rebuilt tranmission was needed. His explanation seemed logical. He indicated that with fluid and filter changes, I might get another 4-6 months out of it.

The trade-off is tough as a trade-in would only get me @ $10,000 so spending something for a transmission is still the most cost effective, provided something else doesn't happen.

This particular "Z" transmission. With a re-build will the same issues be evident?

13th Nov 2007, 18:52


Our 1998 A8 was in the shop at about 85k miles for replacement of the timing belt and assorted tensioners/pulleys, before any timing belt problem could occur. It is usually replaced at about 105k miles, but we didn't want to take a chance after hearing some horror stories of engine damage from early belt failures.

The problem now: after reassembly, the engine started leaking oil quite copiously. The (independent) Audi specialist suspected the front seal and replaced it. Oil still leaking. Now he suspects that that model year's 4.2L engine has a peculiar arrangement in that there's a rear seal that gets loosened when the front is opened to get at the timing belt. He thinks he should have changed the rear seal too, and was just unaware of that for a 1998 V8 Quattro (very honest man, close friend; I'm seeking your advice on his suggestion to see what others have seen.)

He will be reopening the engine to get to that rear seal unless someone has a better idea. It's apparently not the head gasket. He's also doing a dye test with an additive to the oil, just to see if there's another clue as to the origin of the leak.

The car has been great, but did need some refurbishment at this stage - has a rebuilt transmission, new power steering pump, new water pump, new timing belt, new front seal, and assorted related consumables. We're hopeful that once this oil leak is fixed it might run trouble free again for some years :-)

Many thanks for any insight you might be able to offer.



Anyone know if the 1998 4.2L Quattro engine is DIFFERENT from 1999, 2000 and so on? How might I get an engine models/revisions history?

17th Nov 2007, 07:50

When replacing the transmission, make sure you replace the torque converter as well. The problems you are describing regarding over 60 and under 5 mph are typically attributed to the torque converter locking and unlocking.

Bon chance, because many people have problems after they install rebuilt transmissions and make sure you get the appropriate rebuilt. The one I had installed had the serial number removed and now the Audi mechanics are clueless when regarding any help to fix the existing issues. I find it amazing they can't seem to cross reference the VIN number with the type of transmission I need to replace the rebuilt tranny I have now. I work in manufacturing and I know somewhere out there a cross reference exists because of warranty purposes. However, the Audi dealer and Audi of America are of no help to find the information I need. That's exceptionally frustrating for a car that retailed around 65k 8 years ago.

19th Nov 2007, 07:25

5 grand gets you a nice one of these in the UK now, but while values plummet, maintenance costs do the opposite. You can't run an A8 on the cheap.

12th Jan 2008, 08:47

I own a 1998 A8 with 107,000 miles which apparently needs a transmission. The car recently (6 months ago) started hunting for gears, shifting from 2nd to fifth rapidly during stop and go traffic, and stuttering when shifting, mostly between 2nd and 3rd gear. I love the way the car drives and am not sure what to do regarding repair.

I was quoted $3,800 for rebuilt transmission. The car is also leaking a small amount of oil with the fix being approx. $800. The trade values I have been quoted are approx. $3,600. Retail on the car, in proper working condition is $7,500 - $9,500. Therefore the repair costs are more than the car is worth!!!

However, that being said, the price of new cars, or low mile pre-owned used cars, are astronomical My A8 has a luxury and size that is hard to replace for $6,000 (i.e. cost of repairs)! What to do?

3rd May 2008, 15:52

Hello, Transmissions, transmissions, transmissions. To those of you that have replaced your transmissions here is my story. I'm a Porsche mechanic by trade, 356 version not the new ones. My wife calls me at work one day and says her 98 A8 with 110,00 miles on it will not move when put in gear. I go home and try it and it's locked in gear and won't slip to start off. After a brutal rev and jam into drive I get it to the shop. I change the dirty trans fluid and filter and button it up and it does the same thing, life time fill on trans fluid my ass. Take the trans pan off again and remove the bank of solenoids that do the shifting. Each one has a small filter screen that is CLOGGED with metal! Clean them all out and reassemble and it works like new. Have since driven the car another 90,000 miles and still working like new. When changing fluid drop the pan, do the filter and pull those solenoids. I'm thinking a lot of transmissions are being replaced for no reason other than someone not finding the real problem. A happy A8 owner.