I've read some of the posts about replacing the muffler, thanks for the great information. In my case it's a little more extensive, at least the damages are. Initially it seemed to be moving too much and was resting on the left side on the trim, which melted. I was able to raise it up and wire it back where it seemed correct. That was two months ago. Yesterday after a long day of mowing I found it had melted two holes in the plastic mesh on the right side. I'm not sure how or why it did. So beyond simply replacing the muffler I want to make sure there isn't something else happening that needs to be fixed so it doesn't happen again.