The body vibrates at 50-60 MPH(moreso around a gradual curve) under the knees while sitting in the front seat; almost always while going on gradual uphill and much less so going on gradual downhill. It is a light vibration and doesn't require any change in the driving. The tires are balanced, the front end aligned, and several motor mounts have been replaced in recent years. The rubber in the front suspension looks ok according to a mechanic friend. No vibration while braking.