Driver side suspension shaking after I hit a pothole

[tino0217]

I posted this a few months ago when I would hit this certain railroad track doing about 40 miles an hour driver side wheel hit the track first and it would just start shaking I'd have to slow down for it to stop. I put on reinforcement brackets but those do no good unless the mounting brackets for the shock absorber are okay. The advice I got was that the shocks were bad or the mounting upper hall for the shock absorber was elongated the hole is not elongated the pin that holds the shock absorber was loose so I grounded out and put in and put in a number eight Bolt I replace the upper shock mounting pin, I put on new shocks but the truck is still shaking when I hit a pothole could it possibly be the Coil? this is a lowered 71 C10. It's not dropped it's just lowered, does anybody have any ideas what the problem could be?