Pop or Klunk

Hello all. I have a pop or a klunk coming from my underbody. I can hear it almost always when I shut the JImmy off. It does it after about 10-15 seconds of being parked. I have also heard it when I am idling in a parked position. It sounds like it's coming from the gas tank or the cat. It sounds like a can when you put a dent in it but on a larger scale. Thanks in advance, Arnz

My also did that, but i got underneth it and looked at it and the cat seemed to be making the noise so i tightened it down and it fixed it. try this, it might help.

Mine did the same thing. It turned out that the innerds of the cat had seperated. I had to replace the cat. Expensive but it worked.

Is it a rattle?