exhaust rattle

[DefiantSix]

I did a search and I found part of the answer I was looking for.
I put an American Thunder catback exhaust on the car (stock except the exhaust and the whisper lid). After a while I started to get a hollow can rattle under heavy acceleration... Then it started happening more often, at lower rpms... I didn't, and still don't, have access to a welder so I figured the clamps were getting loose. I found the resonator pipe / cat connection was loose enough to move the pipe by hand - so I tightened it. I haven't had the rattle for a long time and now I only get it at high rpm. I keep finding myself under the car inspecting the clamps/pipes/heat shield... Tapping random parts with the wrench I heard a weird rattle from my cat. We have honeycomb cats, not those pebble deals, right?
I also read something about hearing similar sounds from the tips. Pardon my ignorance, but why would it be the tips?

Any and all feedback is greatly appreciated.

[lookout4theyeti]

Re: exhaust rattle

you may very likely need a new cat if you can hit it with a wrench and hear it rattle. Other than that I dont know what else to tell you. My flowmaster rattles like crazy too but its just cause the temporary exhaust hangers i have on that i need welded.

[PalmHarborBlkv6]

Re: exhaust rattle

you may very likely need a new cat if you can hit it with a wrench and hear it rattle. Other than that I dont know what else to tell you. My flowmaster rattles like crazy too but its just cause the temporary exhaust hangers i have on that i need welded.

He is right, U need a new Cat. Convertor.
I had the same sound, brought it to the
Chevy dealer and they replaced it free.

[DefiantSix]

Re: exhaust rattle

So options on a high flow cat.... What brand / size am I looking for, any issues I'd run into, would it throw any codes...? What costs for parts / time for labor am I looking at?