[cory]

at idle and at some crusing speeds i can hear what sounds like a grinding sound. at first i thought my tranny or a rod was going out, but when i parked it in my garage i could still hear it. i got down and listened by the cat and it sounded kinda like rocks were tumbling around inside there. when i shut it off and tapped the pipes it made the sound, and when i hit directly on the cat it made it. bad cat?


edit- that was kind of a bad question, of course its a bad cat

 

[Novi2kRT]

kinda sounds like the material inside could be coming apart.. take it in for an emissions warranty and you should be good to go..