I have a 02 Audi A6 4.2l with the 17" wheel package. I have a vibration in the front end that starts at 50 mph and ends at 60 mph. The steering wheel does not shimmy as if the rotors are warped. The feeling is more as if the wheel is egg shaped when rolling. More of an up and down feeling then a side to side motion. Brakes and rotors are new. I just installed a new set of 18" wheels and tires. Both axles have been rebuilt. The car has approximately 81 thousand miles.

Could this be a wheel bearing, hub or the linkage going bad?

Also, another problem with the car is that I am getting an excessive amount of heat from the vents when I open the windows even though the heat is not on. Seems that some type of control valve is not shutting. Is this something anyone else has experienced.

Thanks.

 

My car has experienced "wobble" for quite some time. I've replaced everything short of the transmission to no avail. I think it is the stub axles getting loose.

Bob

 

The wobble you refer too may be caused by your wheels being unbalanced, a bad or out of round tire(s), or even a slightly bent wheel(s).

 

I have had the car on a lift and sped it up to 55 mph. Wobble is coming from the left rear, not the front.

 

I had the same issue with my 2002 a6 4.2 and replaced struts, control arms, axles, rotors and pads. Balanced the wheels like 10 times but the wobble remained.
I came across a thread in there where someone explained even if you have new tires and balance them, they might not really be round which will cause the wobble. Sure enough I took them to a tire center, replaced the only 1 year tires with brand new continental tires and couldn't be happier. Wobble gone but so were about 800$ in tires.