A car can begin to shake because of engine problems, axle problems or brake trouble. The shaking of a car can also be caused by wobbly wheels or tire problems.
Shaking that emanates from the car's engine typically occurs because the engine isn't getting enough air, fuel or spark. The symptoms to diagnose an engine-related issue include the car shuddering or jerking during acceleration and staccato shaking similar to driving over a highway rumble strip within a specific speed range. The car may also operate smoothly for a while and begin to shake later. These symptoms may indicate that new spark plugs are needed or that the spark plug wires need to be checked. The issue can also be caused by a dirty air filter.
A bent axle or driveshaft, worn out constant velocity joints or damaged boots on the ends of the drive axles can also cause a car to shake. Shaking that begins when the brakes are pressed is typically caused by a warped brake rotor. Shaking occurs because the calipers and brake pads can't grip the uneven surface of the rotor correctly. Shaking can also occur directly through the steering wheel, which often happens when the car's wheels begin to wobble at the hub. Uneven tread on the car's tires, unbalanced tires and tires that roll unevenly can also lead to shaking.