So as I have stated before, I know really nothing about the exhaust system....I know that's where the bad stuff comes out, and that's about it. Oh yeah, and don't breath in that stuff too much. I can't find much talk of the exhaust system in the FSM, so here goes the questions. So I've noticed a rattle on start-up and idle after returning from a trail and upon further inspection noticed the source, the rubber mount just behind the cat is torn. What do I need to replace, the top half or the bottom half, or both. Thanks for your help.