Okay, I was at the dealer a few times over the past few years. I moved to the other side of town and the dealer I bought this from went out of business.

I have been waiting to get brand new tires for my impala so I could bring the car to the dealer and show them that the tires are not the problem. After doing so, they recognized the oscilating vibration and started to replace some front end parts....bushings, motor mounts, a trans axle, etc... these changes only dampened the vibration for a short while for it to only return again and again. It is also important to note that I would experience the vibration more severe when the car was cold. Also, I noticed that when I accelerated moderately, the vibration would completely stop until I was lightly accelerating or holding a steady speed.

Eventually the dealer mechanics began to say that they don't feel the vibration any more and that they can't find anything wrong. After a few thousand miles on my new tires they road forced tested my tires and said that they could not get them into perfect balance...they also started to point out that the front tires were scalloping and that was the cause of my vibration. This was rediculous becuase the scalloping was obviously a symptom of the problem and not the cause.

I like my Impala SS very much except for this annoying vibration. If anyone has some ideas please let me know.