If I'm driving at a constant speed, no problem. When I accelerate, especially at around 45 mph, the car shudders. Feels as if the rear axle is rubbing. It's not severe, but I think it's getting worse. I did have the rear right axle replaced recently. I'm thinking the U-bolt. Thanks for any ideas before I bring it back to the mechanic who did the job.

 

Big guess .... motor mounts

 

best idea is to take it back to the mechanic who worked on it, he would know best what the problem might be.