Hi all, I was just surfing the forum and looking through posts dealing with exhausts and got to thinking about my current setup (stock).
The converter rattles, it has since I got it (although it happened rarely).
It will clatter on start-up sometimes or if I rev the engine it will clatter on the way down. I've read that if it were bad/plugged, the truck should feel sluggish/have bad mileage/or have a SES light. Mine has none of those, it just rattles (sounds like a drum solo on start up). It will get up and go with no hesitation and gets around 18-19 mpg usually with a best of I think 24 mpg. What I'm wondering is this: I've been driving it a year with the noise getting worse, is the cat just going to torpedo my muffler one of these days or something? I never thought too much about it cuz I had/have other stuff to fix first. Sorry if its a repost, but any info is appreciated!
Thanks, Jayson

Sorry, It's a '99 4x4 4.3L

 

I used to work in a muffler shop and I've seen plenty of converters that rattled like that. Make sure it's really the converter rattling. It may be the exhaust is hitting against something. The way I check to see if it's the converter rattling is to hold the exhaust pipe as solidly as I can right next to the converter (don't do this after driving, let the exhaust cool down first, trust me), Then I'll either use a rubber mallet or hit the underside of the converter with my hand. You can tell pretty quickly if it's the converter rattling or not.