One of mine is loose at the clamp to the muffler. Do I have to remove bumper cover and heat shield to get to and tighten the clamp or can I just jack up the rear? Don't want to waste too much time if not necessary.

 

No need to remove the bumper cover.

 

Stick your head under it and have a look.

 

Did, it was pretty tight in there and wasn't sure if ultimately removing the bumper cover was the way to go. Just finished tightening it. Pro tip-- your cats get hot during the 30 seconds it takes to turn on the car and back it onto the 2x4s you need to back it onto to get your jack under the lift points. Watch your arm.