Hello All,

I purchased a 2012 A4 S line a few months back. I noticed around 75-80 mph vibrations are very noticeable. I do not feel anything in the steering wheel, so I figure it is coming from the right rear. I purchased new wheels and tires, they were balanced before I put them on, same result. I had a rear alignment done. Same result. I have seen a few threads about wheel bearings and some about bent drive shafts. The drive shafts appear to be the same manufacturer. The vehicle has about 80k miles, so I am doubtful about the wheel bearings. Any thoughts on where to start troubleshooting would be helpful.

 

Short term, you can move right rear to right front and see if the problem moves with the wheel. If not, ignore next comment.
Speed related vibration almost always is caused by out of balance wheel. Suggest you take them back to the balancer, explain the problem and symptoms, and see if they can balance them high speed.