Q: Why would my car shake while driving?

Hi, thanks for writing in. The first thing to evaluate is the condition of the tires and their balance. If you have a tire defect, such as a belt separation, that will cause shaking at any speed. Tires can also develop flat spots that will generate quite a bit of vibration. The suspension could be loose or worn and that will cause vibration and shaking of the vehicle. Shaking can also be caused by defective motor mounts. Apart from physical inspection of the rubber motor mounts (look for oil contamination, cracks, and rot) if the mounts are defective, you can often see excessive movement of the engine from side to side if you slightly rev the engine in park. The vehicle vibration your are describing can be repaired, and thus I encourage you to contact YourMechanic so that you can get the problem identified and quickly repaired.