It normally means you have a bent wheel or tire out of balance. Have your tires rotated and balanced.
You may have a ball joint going out or your wheels are unbalanced
if it shakes while your braking your front roters could be warped or if it shakes while your driving try balancing the tires at a tire shop.
If your saying it shakes when driving it may be your wheel alignment may be off
Most likely bad tire or a wheel bent, or out of balance
if the steering wheel shakes there can be a problem with alignment. shaking when braking would probably be a brake problem. constant shaking i'd expect you should check the muffler If the front end of your car shakes when just driving normally, your front end probably needs re-aligning. If it shakes when you apply the brakes only, your brake rotors are probably warped and need re-surfaceing. Impossible to answer question, please be more specific. It shakes when... I feel it shake in the steering wheel when... I'm driving along and... etc. It depends on WHEN it shakes. Low speed driving: damaged tire, U-Joint, ignition misfire, burned valve, low engine RPM. Highway driving: loose steering, faulty ball joints, tire balance, bent wheel, tire damage. Engine idle: burned valve, ignition misfire, motor mounts, low engine RPM, dirty injectors, EGR valve... All of the above plus quite a few other possibilities.
yeah ya big idiot!
Usually when the steering wheel shakes badly while driving it could mean a few things. If it shakes only when you are applying the brakes, this means you have warped rotors and they will need to be turned or replaced. If it shakes just while driving, it could be that you have 1 or more tires that are unbalanced. Check this first before proceeding. It can also indicate that a wheel alignment and perhaps steering linkage repairs are necessary.
Tire out of balance, bent wheel, defective tire, or loose lug nuts. Have the tires/wheels inspected, rotated, and balanced.
engine rubber mounts or timin out
Steering wheel shakes
Warped rotors
could be bad alignment