Here are the most likely culprits:
* Ball Joints: Worn or damaged ball joints allow excessive play in the steering and suspension. Hitting a pothole can cause a sudden, violent shift in the wheel alignment, resulting in a shake that only stops when the wheel is no longer moving. This is a very strong possibility.
* Tie Rod Ends: Similar to ball joints, worn tie rod ends create slop in the steering system. Impact from a pothole will exacerbate this slop, leading to the shaking.
* Steering Linkage: Any component in the steering linkage (including tie rod ends, idler arm, pitman arm) can develop play, leading to the same symptoms.
* Wheel Bearings: While less likely to cause a *violent* shake that only stops when stationary (wheel bearings usually create a more consistent rumbling), a severely damaged wheel bearing could contribute, especially combined with another problem.
* Loose Parts: Something might be loose somewhere in the front end. A bolt coming loose on a suspension component, for example, could lead to this type of erratic shake.
It's crucial to have this checked by a mechanic immediately. Driving with these symptoms is dangerous. Ignoring the problem could lead to a loss of control, especially at higher speeds. The mechanic will be able to inspect the steering and suspension components visually and through testing to pinpoint the exact cause and perform necessary repairs. Don't try to diagnose or fix this yourself unless you have extensive mechanical experience.
