I had a shop did four wheel alignment for me on my 99 A6. However the steering wheel still shakes when the car gets up to 120Km/h, although no much. Should I assume this is a bad alignment job? My front control arms are tight and the tires are 2 years old, don't see anything wrong on them.

I didn't think alignmentwas hard to do if you have the right equipment. Is it possible that something else in my front end is bad?

The frontwheels are either out of balance, rims are bent, or the front tires have a seperated bead. Have someone put the front tires on a balancer and they will be able to tell you whats wrong with them hopefully.

Thanks Auditech79. I took the car to the high way again today. It does feel better than before when it is at 120; but it still shakes a little bit when it bring it up to 160 and sometimes I feel the shaking is from the back of the car. Also, sometimes the wheel shakes a bit and after a few seconds it stopped shaking.

how often should I balance the wheels??