Why does my 1989 shake violently when I go over a bump in the road on 1990 Mercedes-Benz 420SEL

I've had a wheel alignment and balancing. It does fine at speeds so far up to 70mph. but hit a bump or pothole and it shakes terribly.

2 answers 3 comments
Your steering dampner has failed
Thank you!! How much should the repair for a steering dampner cost? Will I damage my car if I drive it for about two weeks?
replacement cost parts and labor $170.00 you should be ok but slow down until you can afford the repair
I would suggest to have the alignment double checked making sure the caster setting is correct.
okay, thanks!