My son just told me of a problem with his 2000 GT Convertible. He said that at a slow roll it feels like he's on a gravel rd. I drove the car myself and sure enough he described it to a tee. Tires seem fine and the car shifts out great(auto). Has anyone else heard of this. If so, what are the remedies?

 

Could be u-joints.

 

Is it in the steering wheel or the seat

 

Seems to be from the seat. I think it's separated belts on the tires. Just not sure.