Things such as steering linkage, shocks, steering dampers and suspension components do not VIBRATE. They can TRANSMIT vibration.
The SOURCE of vibration has to be a rotating part. In the case of vibration felt in the steering wheel it is a 99% certainty that it is tire or wheel related.
Proper balance does not always take away such vibration. BTW to PROPERLY balance wheels, weights must be used inboard AND outboard on the wheels.
Even if properly balanced tires can cause terrible vibration if the have excessive road force vibration (stiff spots.) The only way to identify such a problem short of replacing the tires is to find a shop with a Hunter GSP9700 machine. This machine can check for excessive road force variation.
To find one in your area go to www.gsp9700.com and click on the locator.