Click/Rattle While Going Washboard Surfaces
 

I had a fender bender a while ago where the car was hit mostly on the front right wheels, tires, and fender area. The car has been making rattling/high pitch metallic clicking noises (sort of like coins in a tin can) when going washboard surfaces randomly in the front driver side and can be almost felt through the steering wheel. At times it's a constant rattling, while other times it is not there. Going over extremely rough roads doesn't necessarily yield the sound, but the occasional turning of the steering wheel will cause a single rattle. I've taken it to 7 different shops to try to duplicate the sound with no apparently solution. The insurance company needs to be able to relate something back to the accident to payout for the repairs. The tie rods were checked and play in the steering was also inspected with no issues. Could it be some kind of shaft problem connecting to the rack? The shop I trust said they can take everything apart but that would cost tons of labor, and there is no guarantee that the insurance company will pay out for the work. Can anyone tell me how I should proceed or start with?