2002 Subaru Legacy Catalytic Converter

Hi Everyone,

I have a 2002 Subaru Legacy with 125,000 miles on it. The PO420 code has been coming off and on for about a year. It is now coming on more consistently. I have received replacement quotes from $500 up to $1,500. The dealer is obviously the most expensive option and will use OEM parts. The other mechanics use after-market parts (some with 2-year warranties and some with 30-day warranties). I am not excited about the $1,500 put I don’t want to be penny-wise and pound foolish. I will spend the money if it lasts longer. I am planning on keeping the car as long as possible.

Thoughts? Can I use after-market parts or should I just go with OEM?

The EPA requires that all aftermarket catalytic converters be warranted for 2 years/24,000 miles.

The OEM catalytic converter must be warranted for 8 years/80,000 miles. And that’s why the OEM costs more.

Every catalytic converter I’ve replaced was with an aftermarket converter. And I’ve never had a problem with any of them.

And just because they come with a 2 year/24,000 mile warranty doesn’t mean they only last that long. I’ve installed aftermarket cats in vehicles years ago. And they’re still on the road with no Check Engine light on.


+1 @Tester

It’s the rear oxygen sensor(s) that are throwing the P0420 code, not the cat itself…So I would replace that first and see what happens…You should replace it/them anyway so it’s not wasted money if the problem persists…

Thank you, Tester and Caddyman! Great advice!