You can tell if they put the spring pad in by visually inspecting it (get down there!) You should be able to tell which pad is in there the same way by the tiny bumps on it. I have to agree with Spiderman its probably a bad link. When you look there should be only one factory bent link on each side near the back. If any of the others are bent then you may have found your problem. Worse case scenario is the chassis could be bent from the accident.