Got oem rear end links installed yesterday and tech also pulled out my two rear shocks to inspect for damage. After I left the dealership I started getting a rattle from what seems like the passenger rear strut section only when driving on the highway at about 70-80mph. Could this be due to a bad install, shock mount, or shock? I also noticed he used some sort of impact gun to tighten the shock mounts bolts on top of the shocks if it matters. Any ideas?