You can identify the problem by diagnosing the vibration of the car. You can try to test-drive your vehicles. Then, you have to determine if the vibration is due to the engine, tire, drive train, or the exhaust issue. To determine this, you have to feel the vibrations of your car at the idle state. However, there are some steps you have to do to feel the vibration through the test drive so that you can make a proper diagnose.
The first thing to do is to test the front tires for a side-to-side or lateral vibrations. Do it at slow speeds and jack up each of the tire individually. Then, grab the tire on the bottom and the top and rock it. If you find any play while you move the tire out and in, you need to replace the bearings either of rear wheel drive or of the front wheel drive. Also, see whether there is a significant damage on the tire such as bulges outside or inside the tire.
Then, increase the speed of the vehicles at 45 miles per hour and see the front tires. If you feel the vibration at this speed, you have to balance the tire. You can go to the tire shop to get it done.
The next thing to do is to test the engine for the vibrations. Open the hood and then start the engine. You will need an assistant to monitor the engine. Ask him/her to stand on the side of the car and tell you what is happening, whether there is broken mounts or not. Also, put on the emergency brake. Then, place your car in drive while you press the brake medal firmly and step on the gas slightly for about two seconds but not more than 2000 RPM. If the engine lifts up or rocks, the mount is bad so that you need to replace it. By replacing the bad mount, you will be able to reduce the vibration in steering wheel.
The fourth thing you need to do is to check any possible vibration which does not affect the steering wheel. Put the transmission in neutral and then let the door open. Then, rev the engine at 3000 RPM. If you can hear the vibration in the middle of your car, you need to check the shield of the catalyst converter. It possibly gets bent or contacts body or converter.
