I drive a 1998 Audi A4 Quattro and it seems as though my car is shifting from side to side while driving and I cant figure out what is the problem. This happens when I hit a bump while driving and the car will quickly jerk to either side in the rear. Also, while driving in the snow the car will sway from left to right, a small tail whip from side to side as if the rear tires were spinning at different intervals. I recently had both of my rear tire bearing done, can the new bearing be the problem? It think the car drives more strait under conditions of the cause while i give it more gas.

 

Could be as simple as getting a 4 wheel alignment...

 

If you have Quattro, inspect the rear inner CV joints. Straight line instability can be caused by worn inner joints.

 

Do bad CV joints make any noise? When I had a subaru the bad CVs made a clicking sound when turning? By the way thank you all for your input

 

The Outers click because the bend angle is considerable. The inners are at a gentle angle and vibrate and shift when they're worn.

 

Could be the diff. I had a chevelle and the rear end was going out. Didnt sway like you are saying, but it sure did have a lot of play. Have you tried wiggling the rear wheels with your hands??

 

I'd jack up the rear and have a friend wiggle the wheels while you look at suspension and drive-train components.

 

^ +1 to looking at the suspension. Your rear struts could be blown causing slight changes of direction to be amplified.

 

yaaaaay for wiggling haha

 

There is no play in the rear wheels. There is some play in the right front wheel, up and down play, because one of the metal rod component is moving. Must have hit something can't remember what . I wonder if the problem in the front is causing the movement in the rear?
Also, I think I may have a problem with the right rear suspension strut because it makes a bunch of noise when going in a pothole etc. Will check out the strut first. Anyone have any ideas on how to test the suspension strut?