I have a 1998 A6 2.8 2wd auto/tip. I'm getting a horrid shake as I drive the car. It only seems to happen at certain RPM's and at different speeds. I've isolated it to the point the car shifts gears. If I place the car in tiptronic, and shift aggressively the shake is almost not present. If I leave it in auto and driver regularly it shakes at what seems to be the point it shifts gears.

I have just bought it recently so don't know much about it. Can somebody tell whats wrong with it?

 

Does it shake at all shift points, even say 4→5?

 

I'd check your front axles. I had a lot of vibration and a good portion of it went away when I replaced the front axles. After that, I still had some vibration when I was on the brakes, but that went away when I replaced all of the front controls arms, TRE's, and SB end links.

My theory is that if the axles are sloppy, when you're accelerating, the load on them reduces the vibration. However, when the car shifts, it unloads the axles and they can move around again until the next gear engages and the slop is taken up. I'm almost sure that the axles I replaced were the original ones, and they had over 200K miles on them, so they were pretty bad.

 

Yes it does only when it shift gears(Automatic) 3->4 or 4->5 or 5->4 or 4->3.
If i go from 0 to 60 on a stretch it runs fine, but when you slow down from 60 to 40 and the from 40 and up. 50+ is fine since it is in top gear. Only when it has to shift gears it shakes.

 

mine makes pretty bad noise only when i gear it from parking to D or R or vice versa, and i checked it already and are the the Upper Links that need to be replaced, (you might check lowers too) so you might check that out. hope that could help some...

 

2WD=> CVT?
If this is the case - embrace yourself!

BTW - what is the mileage?
Any change if you rotate the tires?
Do you feel the shake in the steering wheel or everywhere?
Is the shake
-longitudinal
-across
-mixed

 

Ive got some of the exact problems your mentioning. But when i put it in tiptronic and keep the RPMs higher than 1800, it has no vibrating at all. Are Audi transmissions just not that good?