Popping sound when turn off engine

[BigClay]

Recently, everyime I turn off the engine, and get out of my Yukon, I hear a popping sound. It sounds like metal cooling, and from best I can tell it is coming form the muffler.

Anyone else ever had this happen?

If my muffler is going bad, what would be a good muffler to get that sounds good, but not too loud (this is my DD and family hauler)?

2004 Yukon XL Denali 6.0

 

[scribble]

Almost all exhuast's do this at one time or another. I had a car in the shop recently that sounded like Sheldon knocking on Penny's door every few seconds.

 

[Schwabotage]

Mine does this. It started after going through an automatic car wash. When my muffler gets hot it pops out to the normal shape and then when it cools down, the bottom pops up leaving a nice fist-sized dent in the bottom. No harm, just annoying. Gives me a reason to get a new cat-back system lol