Don't forget simple bushings. My lower ctrl arm bushings were bad, and my symptom was lateral motion over bumps and the sensation that the front wheels were being hit with a hammer over bumps. New bushings and all is well. In fact, once the bushings were replaced my steering wheel shook so badly I had to get the tires balanced - evidence that the arms were totally out of contact and not transmitting that much feedback to the steering wheel.

__________________
former: 83 300D, 97 C230, 93 400E

current: 08 C300 Luxury , 92 500SL