so i got my new exhaust. pacesetter headers, magnaflow cat (direct fit) and the pacesetter kfx cat back...my problem is the cat seems to have a rattle comming from it...not sure what it is all my clamps are tight it seems to be coming from inside the cat... when i started up the truck it had a odd smell is that normal or does my magnaflow cat have some plastic in it i forgot to take out lol

 

I believe there is a bit of a break in time for cats, where you will get a funky smell at first. I don't know about the rattling, though. New mufflers also take a few miles to break in.

 

A rattling sound is USUALLY the cat breaking apart.

 

ok makes sense it isnt terrible just a odd sound and a odd smell i took it for a drive the cat stopped making noise at one light then the next mile it started again... i know its not a hanger loose or a clamp

 

Does it sound like you have marbles in your exhaust?

 

Are you sure it's not the heat shield rattling? I've had several break at the spot welds and they rattle like crazy.

 

^ Good point.

 

no all my heat shields are tight it didnt rattle before i put the new exhaust on... it does sound like marbles rattling around

 

I'm talking about the cat heat shields, not the ones on the truck. It's very unusual for a brand new cat to break up.

 

i just crawled under there and nope i shook the crap out of it and no movement or rattles who knows i guess i will drive it and see if i can get it to work itself loose