2005 Suburban, 5.3l, 2wd, 1/2 ton, 72,000 miles.

This week, the truck developed a "buzz" coming from underneath towards the rear. It has gotten worse through the week, at first only intermittently, and now does it consistently at certain RPM's. I can get it to do it continually 31mph.

I crawled under it to inspect, suspecting a heat sheild. The heat shield that is integrated into the muffler itself is cracked along the edge where attaches to the mufflers, and that's what is buzzing.

Anybody ever experience this issue and if so how did you repair it?

Thanks in advance for replies.

remove it

That's what I was planning to do but didn't know if it served any special purpose.

the only 1 i dont like to just remove is the 1 on top of converter.should'nt have any issues with removing 1 around a muffler unless its close to gas tank

remove it


do not remove it....It is best to rap a s/steel wire around muffler to stop the noise and maintain the heat shield....removing the heat shield can cause other issues.. I use .050 wire works very good and will never fall off use electricians pliers to twist and lock in place..

heat shield is there for a reason . you don' t want you're carpet to catch on fire while driving down the road do you? exhaust temps. run hotter in newer vehicles due to stricter emissions requirements. tie it down temp with wire ,get to a weld or muffler shop to tack it down permanently.:popcorn:

yes do not remove it! either wire tie it or secure the corners with jb weld or sheet metal screw it to the underneath has been know to do the trick