What can cause the steering wheel to shake?

Check all linkage for wear or play,jack under each a-arm one at a time ,move tires left to right for linkage/ up and down for bearings & ball joints and cv axles if you get play or pop's and clicks have some one follow the noise. Shake's during braking, rotors are warped due to hot rotors hitting cold water puddles on the road. Shakes to the left or right,if the steering wheel shakes to the left put the left front tire on the right side, test drive if it starts shaking to the right that will be the bad tire,vise-versa if shakes to the right .Replace that tire and get a alignment check,steering wheel shakes are front tires,the whole car skaking is the rear tires.This is due to uneven wear on the tire the eye can't see. WORN CVC OR U-JOINTS, UNBALANCED TIRES( COULD BE CAUSED BY LOSS OF A WHEEL WEIGHT, MUD OR SNOW IN YOUR WHEEL), BENT RIM, ECT. If you have directional tires make sure they are on the right sides LOTS of THINGS; First define when it shakes and how it shakes. Tires at highway speed; tire balance / improper wear (may be alignment issue). I have had intermittent vibration from using a different tire on front. When Brakes are applied: front rotors warped (worst at higher speed)but I have found numerous steering linkage issues (vibration at slower / not all speeds). Steering Linkage- vibration when hitting bumps on highway: tire rod ends, idler arm, pitman arm, panhard rod ends (if equiped), ball joints, could also be worn steering box (usually hard steering issues). There could be suspension issues like a damaged strut (not just worn-out). Checking: No engine, running get under front end and have someone turn steering wheel lightly back and forth, any joints should move in tandem (no looseness). You'll look for movement that is not consistent. Another way is to bottle jack under lower A arm on one side / get wheel off ground, grab wheel and move laterally back/forth from outside vehicle. There should be no play or noises when pulling hard. THEN put tire iron under wheel and pull up. Wheel should move vertically without shifting. This checks ball joint play. Look for inconsistent movement of wheel. Some have upper/lower ball joint, some have lower ball joint/strut. Sorry, does take some experience to know what is acceptable. If it bad problem it can be seen. Service manuals sometimes describe maximum movement for the technicians. Diagnois FIRST before replacing parts.

Often, this sort of an issue crops up when your wheels are inappropriately balanced, or the tires have worn unevenly. But sometimes loose bolts of the wheel or a distorted brake rotor could be the culprits. In case of a disfigured brake rotor consider replacement. The other issues can be taken care of by an expert. You can learn more about it Automotive-online.com