[summitrider04]

I will have to replace my catalysts and since I'm in CA, it's expensive. I have 145,000 miles, although they failed probably around 125k. Is this normal? I will have to replace them to pass smog, however, is there something that caused them to fail? Would hate to spend the money only to have them fail again for my next smog in 2 years.

My truck is well-maintained as far as spark plugs, air filter and oil changed regularly. Have read a poorly running motor can ruin a cat.

Thanks!

 

[smj999smj]

They tend to become inefficient over time, that's all. Yes, a bad running engine can ruin a converter, but sometimes they just go bad on their own. I've replaced both of my front converters on my 06 Pathfinder. Check with Rockauto.com; I believe Walker makes C.A.R.B. certified replacement catalytic converters that are a lot less expensive than genuine Nissan parts.

 

[kgordon]

They can and do reach a point where they fail. Though i would think the average is around 125K or more. That said, i had one fail on my 2011 last spring. It was fixed under warranty and i am not really concerned that the others will fail early.

You don't say what kind of truck you have but you could and probably have 4 cats. If one of the front cats goes it will put more strain on the secondary and you should get it fixed as soon as possible as it will impact the longevity.

 

[summitrider04]

Thanks for the replies

My truck is a 2005 King Cab Nismo with the 4.0L V6. I'm pretty sure it has 4 cats also...

Here's a question: All the catalytic converters sold outside of CA and NY are so cheap - if I installed a set of out of state cats (or high flow cats) wouldn't it get rid of my check engine light and pass smog? Last time I had it smogged, they just plugged it into a computer and didn't even start the engine...it would prob fail a visual inspection if they got under the truck.

 

[pdxfj]

You will fail a visual if they look under the truck at your out of state cats. The inspectors will look up part numbers to verify they are either OEM or approved CARB aftermarket.

I'm not in California, but know people who are and some of them have been under the microscope numerous times for smog inspections.

 

[smj999smj]

The C.A.R.B. certified aftermarket converters will come with a sticker that states they are such to be installed in the engine compartment. Looking at Walker's catalog, it doesn't look like they make C.A.R.B. certified converters for the 2005-11 Frontier V6. Your only option might be genuine Nissan or emission-certified, used converters.

 

[summitrider04]

Yeah, I think I'll end up just spending the money and replacing both cats with CARB approved OEM parts. Total bummer on how expensive it is.

 

[kgordon]

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Yeah, I think I'll end up just spending the money and replacing both cats with CARB approved OEM parts. Total bummer on how expensive it is.

Do you know that both are bad or just one? I would only replace one. No telling how long the other might last. Take that money for the second and put it in the bank and save it for when you need it.