Heat shield noise

[mhawk4295]

I have a 2003 z66 and it makes a god awful noise sometimes when taking off from a stopped position, sounds like the heat shield on the muffler is rattling. I searched the forums and could'nt find anything on this problem but am sure I seen it on here before. It might have something to do with a sensor ring? Any help would be nice........Hawk

 

[merkava]

I just had my 2004 2wd at the dealer for the same thing. The weld holding the heat sheild to the muffler began to crack (from shrinking and expansion) causing an occasional noise. There is a TSB covering it. They say to replace the muffler or remove the heatsheild and reattach it w/ metal bands. The dealer bent the edge back where it was cracked. That stopped the noise. Hopefully it wont crack further.

 

[moosc]

there is post on this problem Gm has a tsb out to replace the heat shield it sounded like popcorn... then month after gm fixed it i switched exhaust.... the fix is a new heat shield with bands