[phillyg]

I'm understanding one of the clips that surrounds a spring pack, on on end, has failed. I'm not understanding how that would make the big jolt and bang you describe. If that's the problem, a few hose clamps might make it safe enough to drive. I recommend, however, doing a further examination to see if a spring mount or bolt has sheared. Another possibility is that one of your brake drums was bound up and suddenly released. When that happened to me, just one time, I was outside the RV and I nearly jumped out of my shoes.