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My mechanic says it will be a miracle if both of my catalytic converters make it past 160,000 miles. I’m 10,000 miles away. California emissions required. Is there any way this is less than a $4,000 repair when it happens?
I was getting a code about inefficiency but that stopped, it was just my mechanic warning me that in his experience they go bad after 150k and it’s a pricey repair that may not be worth it.
If you properly maintain your car and keep up with the recommended maintenance and address any check engine lights and faults as they pop up you should be fine.
The cats are not that expensive if you go aftermarket and have a muffler shop install them. If you have one reading inefficient on ocasion it will not get better or heal itself. Replacement is the only way to truly fix it.
The cats are not that expensive if you go aftermarket and have a muffler shop install them. If you have one reading inefficient on ocasion it will not get better or heal itself. Replacement is the only way to truly fix it.
I would've thought welding in aftermarket ones would be an option? They are a dumb component after all. As long as the 02 sensors read the correct value.
Edit : I've just realized I have repeated what you e just said. I'll leave my comment in so you can poke fun at my old weary eyes etc 🤣
Yes I assume you could probably get away with welding in new ones also.
I bought mine at the site above because I didn't wanna try that plus in my state a exhaust shop won't modify any exhaust that had factory pollution controls. Damn laws and rules suck 🤪
I was getting a code about inefficiency but that stopped, it was just my mechanic warning me that in his experience they go bad after 150k and it’s a pricey repair that may not be worth it.
I'm my state is legal to sell cats to a junk yard or recycling place. Add long as you have proof they aren't stolen like a recipt for a new one or from a muffler shops etc.
They are valuable even as scrap.
Last edited by RobertR728; Dec 21, 2025 at 07:46 PM.
I'm my state is legal to sell cats to a junk yard or recycling place. Add long as you have proof they aren't stolen like a recipt for a new one or from a muffler shops etc.
They are valuable even as scrap.
Yes, John Q Public can sell used cats for scrap, and that can be pretty good money. But I'm sure what @atikovi was saying is that junkyards / auto recyclers can't sell used cats to John Q Public to install on their vehicle. The U-pull-it yards near me cut them all off the cars as part of their in-processing before the cars go out into the yard.
Seems the EPA has restrictions on installing used cats and they have to be tested and properly labeled which I doubt anyone will go thru that trouble. And then certain states have additional laws about it. Im in MA where they test for emissions so im sure the laws on salvage/resell/install are long.
Ive seen new aftermarket replacements for around $400 simple bolt on. Can find used "downpipes" for around the same price. No idea how good they are.
I havent seen cats failing being a big issue. They are expensive parts just because what they are made of so it is important to maintain the car in good running condition. Make sure to address anytime the check engine light comes on which indicates possible damage to the exhaust.
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
