Cat Converter

[AFD256]

What are some sign/symptoms that your cat converter is going or gone? What would the truck be doing? and how bad is it to change?

[ATMINF]

They normally last well over 100,000 miles as long as you truck has not been running rich or lean for long. Normally he way you can tell is the lower amount of power because it gets "clogged up". Basically you can have the interal part melt and you can hear stuff rattleing around, or you will throw codes from you o2 sensors. Hope this helps, Good Luck!

[Mark_in_Tulsa]

All cats are warrantied for 8 years or 80,000 miles, which ever comes first.

So if your under that then go back to your dealer.

[AFD256]

Thanks guys, Yeah I got my truck inspected, and also mention the rattle thinking it was a heat shield or something. That's when my guy told me it was the cat and it would be $750, Gm said at least $800+. It doesn't look that hard to change out, bolt on bolt off. I can see maybe the bolts be s**tty to get off. Napa quoted me $480.00 for a direct fit. Anybody ever change one? how bad was it? any hints?

Thanks

Chris

[CHVYPWR]

Try http://www.discountconverter.com/ I got the cats/x-over pipes for my '98 there for $250 shipped!

[dichdoc]

I thought my cats were bad, I'd pound on the cross over tube and hear what sounded like rocks in the tube. Took it to a good muffler guy and he pulled the O2 sensors and isolated them. The rattle was gone. I had read about epoxying the little shield on the sensors but opted to replace them with new ones. All is quiet now. My big concern was what would cause the cats to fail. TB

[cruise1977]

Hello. I'm new to this forum, just found it today. But I recently had to change my cat converter. My truck only had about 105,000 I think when it went bad. It has the 4.3 V6. It was giving my )2 sensor error codes. The downstream one. It was also missing a lot on the highway, especially when trying to get up a steep hill around 65 MPH. Eventually it couldn't get down the highway without missing, and had almost no power. I knew when it was missing because of the flashing light on the dash. I never heard any ratteling noises though. I was surprised that the cat went bad with so few miles. I mostly drive highway miles.

 

Josh

[svensk]

Hello. I'm new to this forum, just found it today. But I recently had to change my cat converter. My truck only had about 105,000 I think when it went bad. It has the 4.3 V6. It was giving my )2 sensor error codes. The downstream one. It was also missing a lot on the highway, especially when trying to get up a steep hill around 65 MPH. Eventually it couldn't get down the highway without missing, and had almost no power. I knew when it was missing because of the flashing light on the dash. I never heard any ratteling noises though. I was surprised that the cat went bad with so few miles. I mostly drive highway miles.

 

Josh

I'm getting the downstream cat codes p04030 and 4020 if I remember right. Once I have the time I'm going to replace the downstream sensor just to make sure that's not the problem before I pull the cat. I had my manifold O2's go out over the winter and I drove for a while with them running rich so who knows...