How long will a catalytic converter last?

awesome, thanks!

I don’t believe their getting clogged. I can smell that it’s running rich. Whenever I find the time maybe I can grab two good cats off of a TW member or a pick and pull (if that’s even legal) and see how it does. I know I have to replace my downstream sensor because it throws a code. It’s only during start up. I have the sensor, it’s just that the threads are junk. I’m probably going to have to order the sea air flange from LC engineering and have my local exhaust guy weld it on.

 

Yep same with both of my older ones in excess of 300K One of them had the O2 sensor nuts rust off and blew the sensor out of the pipe but that was about it.

 

I pulled my old O2 studs and replaced with new 8mm x1.25

 

I thought they were welded to the flange? So I could spray some Aerokroil on them, remove them and replace with new ones?

 

Catalytic converters should last indefinitely assuming your truck is in good working order. Lean and rich conditions kill cats. Also, thieving tweakers...skids work well to protect you not only from rocks but also cat thieves

 

Yes. The studs thread into flange. I used Vice grip locking pliers after one stud broke leaving 3/16" sticking out so I replaced both studs with new 8mm x 1.25

 

Kinda like our trucks...

 

That's right

 

I have no comment in response to your cat question, but you seemed to be considering replacing both sensors. While I’m sure some disagree, if you have the money I have always replaced both the down and upstream sensor at the same time. (Unless you previously changed them at different times). Just extra peace of mind imho, especially if you’ve thrown some codes before. Quicker, cheaper, simpler than replacing the cats

 

I’ve actually had to replace both the up and down stream sensors twice but not the cat.
These sensors get caked with carbon, this helps them fail

 

I’ve never had a problem with my cats either, although I have 220k on my truck. Replaced my sensors about 20k ago. Think if I was you OP I’d throw new sensors on both locations and call it a day