Tire misalignment is one of the most prominent reasons for a vibrating steering wheel. It takes your car to the mechanic, for the alignment is a step in the right direction. Depending on the vehicle you're driving, the wheels and axles are adjusted to ensure they're moving in the same direction. However, there are many reasons why it shakes when you hit the brakes. If you continue to experience shaking even after the alignment, your issue probably lies within the braking system.