I started a road trip today and stopped at a Rest Stop. Had had no problem. When I left the Rest Stop, I was driving at 60-65 mph when the car suddenly started shaking. First thought it was the road, but it became clear that I should get to a mechanic. Was near a middle sized town in Maryland so went to Chevy dealership. I was told one or maybe both break pads, sorry don't know if front or back, needed replacing as well as the calipers. With diagnostic and flushing brake line, the cost will be $1350. Has this shaking ever happened to anyone. Tires seem to be fine.