occasionally when driving or idling my truck has a clicking that I believe is coming from the cats, what would cause this?

 

The cats heating up,i beleive it is normal,mine does it too

 

thanks, i guess i won't worry about it then

 

ditto--mine has made that sound since brand new,so I don't think it's anything to worry about-----I hope!!!

 

hmm... to play it safe check your heat shields they might be comming lose.

 

This is common on all vehicles equipped with catalytic converters.. It is the heating and cooling of the total exhaust system. Especially the honeycomb material that lines the inside of the the catalytic converters... You will notice that a vehicle exhaust will tick and ping once the motor is turned off...You will notice it on the new vehicles more so than the older vehicles....

 

I've always noticed it after turning it off, but it's a little different noise when driving. maybe it's always been there, but I just noticed it recently, probably cuz it's warm and I'm driving with the windows down lately. thanks for the replies though

 

after doing some more research here the noise seems to be consistent with noises people have heard right before their cv's go out, so I'll be looking into that next time I have some free time