On our '06 Malibu the headlight beams were jittery while the rear bumper cover was rattley. The Chev body guys rolled their eyes and said the light fix was the wrap the headlight housings male plastic pins with duct tape until they fit the female slots tighter and to roll up duct tape inside out and stick in between the bumper cover and rear fenders. It all worked, but just think what a change for a long time body man.