I have been noticing my cats have been rattling lately..Could that mean my cats are going bad??

 

probably either a chunk of exhaust crap or a piece of the honeycomb inside broke loose, how many miles on them?

 

34,954 miles

 

thats really low to have problems with them going bad, any computer codes tripped about them not working??? you sure its the cats or could it be something else around them making the noise?

 

are you sure its actually the cat rattling... i thought mine were for the longest time.. but it was a little metal ring piece over the end of my o2 sensors that were rattling back and forth, drove me nuts. Go underneath there and see if when u hold the o2 sensor if it still makes the sound.

 

Usually rattling is the heat shields. It takes running pretty rich for a long time to kill OEM catalytic converters. It's possible they're coming apart but they'd almost certainly have to have overheated to be going with that few miles.

 

i had that rattling noise and it was my cats. the cat on the drivers side was breaking on the inside and my truck started running sluggish. It sounded like i had a rock in my exhaust pipe. mine went out with about 55,000 miles. the ses light also came on and tripped a code for it.

 

I had a magnaflow cat go after only 4000 miles. It made a real bad rattling sound - like a bag of rocks - as it died. There are no moving parts in a cat, so once they make that rattling sound they are fubar. Replace it and try to find out what caused it to fail. I think OE cats are warrantied by law for at least 7 years.

 

I had a rattling under my truck a couple of times.

First time, heat shield, needed tightning.

Second time, catalytic converter. Pipe leading out the cats was vibrating and the dealership added a hanger behind the cat. Cats warranty in California are bylaw 70K or 7 years.