Aftermarket cats? (Subaru)

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Helping to source a replacement cat for a '02 Subaru Forester 2.5.

OE part, as expected, is close to $1000.

Found some aftermarket alternatives for between $300-600.

Cats are generally one of those items where you get what you pay for; can't really substitute or disguise the lack of the precious metal primary components.

But, I'm still wondering if some of the more reasonably priced alternatives are still acceptable, if not quite the same standard as OE?

Not gonna throw money away on a $200 cat. But a $600 part like the DEC, or something from Magnaflow, Bosal or Walker might be fine?
 
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Carsound/Magnaflow are probably the most reliable. They sell a lot of "direct-fit" OEM replacements.

Tons of Honda guys tried different brands and they always blew out a year or two later.
 
i wouldnt want the red light oon the dash, or the car constantly throwing codes for lack of a cat.. two pennies
 
There are a lot of aftermarket cats that will shortly (6 months or so) trip the CEL.From what I gather,Subarus need a computer flash done when converters are replaced (especially aftermarket ones).You will get the dreaded "Converter inefficiency" CEL otherwise.Something weird about Subarus...
 
Try cleaning the Factory cat first before replacing it.

I've had good luck with soaking them overnight in sudsy water with laundry detergent.
I've also heard of people using a gallon of laquer thinner to 1/2 a tank of gas and driving at high speed for 50 miles or so.
Scotty Kilmer has a video on this. (Check youtube for the video)
Though I've never tried this method, and he seems like a hack sometimes, but other times his repairs are spot on.
 
The guys on Car Talk had someone call in and say they used an after market cat on a Subaru. It was a $600 cat and still was throwing codes. Perhaps they did not know what NHGuy is referring to.
 
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Makes me very happy my Subaru's CCs are covered for 15yrs/150K miles! (PZEV warranty)

Joel
 
Originally Posted By: NHGUY
There are a lot of aftermarket cats that will shortly (6 months or so) trip the CEL.From what I gather,Subarus need a computer flash done when converters are replaced (especially aftermarket ones).You will get the dreaded "Converter inefficiency" CEL otherwise.Something weird about Subarus...

Yeah many auto manufacturers set the cat efficiency CEL oversensitive at 95%, far higher than the state smog test. So in many cases the cat efficiency CEL is merely a spend money light and nothing is wrong with the cat. Reprogramming the efficiency to a lower efficiency is one way, another is mod the sensor thats taking the reading for $6.
 
Originally Posted By: LeakySeals
Originally Posted By: NHGUY
There are a lot of aftermarket cats that will shortly (6 months or so) trip the CEL.From what I gather,Subarus need a computer flash done when converters are replaced (especially aftermarket ones).You will get the dreaded "Converter inefficiency" CEL otherwise.Something weird about Subarus...

Yeah many auto manufacturers set the cat efficiency CEL oversensitive at 95%, far higher than the state smog test. So in many cases the cat efficiency CEL is merely a spend money light and nothing is wrong with the cat. Reprogramming the efficiency to a lower efficiency is one way, another is mod the sensor thats taking the reading for $6.


Nice post.
I believe the MOD you refer to is stacking 2 anti plug foulers, and putting the second O2 sensor on top. it works well, and is cheap.
If the cat is really OK, no harm, no foul. A win win.
 
Originally Posted By: LeakySeals
You mentioned throwing away money on a cats, can I as why you need one?


I'm trying to find out. The car and owner are thousands of miles away.

This is one of those Subaru 2.5s that had the issues with the head gaskets, so it could be related, or due just to old age.

The primary objective is to see if a little money can be saved, on an aftermarket part.
 
I had to replace a Cat on my wife's truck. My research a few years ago revealed that aftermarket cats only are required by law to carry a 2 year 24K mile warranty. Many cannot be sold in California for this reason. Aftermarkets are cheaper because they contain less precious metals. It is not legal to replace an OEM cat with an aftermarket cat, if the OEM cat has not failed. I wish I had kept all the papers I collected on this, it was rather interesting. I was rather turned off on aftermarket cats after reading this info. You get what you pay for, so it depends how long you plan to keep the car.
 
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Walker cats are pretty good. They are the OEM supplier to Toyota and possibly others. I don't know who makes Subaru's OE converter though.
 
Walker only supplies some of Toyota's exhaust, Futaba is the main supplier for Toyota, and they make the majority of the Cats.
 
Originally Posted By: Carmudgeon
Helping to source a replacement cat for a '02 Subaru Forester 2.5.

OE part, as expected, is close to $1000.

Found some aftermarket alternatives for between $300-600.

Cats are generally one of those items where you get what you pay for; can't really substitute or disguise the lack of the precious metal primary components.

But, I'm still wondering if some of the more reasonably priced alternatives are still acceptable, if not quite the same standard as OE?

Not gonna throw money away on a $200 cat. But a $600 part like the DEC, or something from Magnaflow, Bosal or Walker might be fine?


We use a lot of Walker direct fit cats, however being in Calif it is hard to find aftermarket cats for a lot of cars. If your Subaru is located in Calif and is a Calif car OEM may be your olny option.
 
Originally Posted By: Carmudgeon
Originally Posted By: LeakySeals
You mentioned throwing away money on a cats, can I as why you need one?


I'm trying to find out. The car and owner are thousands of miles away.

This is one of those Subaru 2.5s that had the issues with the head gaskets, so it could be related, or due just to old age.

The primary objective is to see if a little money can be saved, on an aftermarket part.

Are you throwing a catalyst efficiency code? Its really just a "warning light". Cats probably fine, just high efficiency ECU settings on newer cars. A minor adjustment can turn the light off.
 
I have exactly this problem with my 2001 Impreza RS. I'ts had the P0420 code come and go for years. I've got two new O2 sensors for it but I can't get he old ones out. And now that the heat shields are rotting off and rattling, I bought a Walker cat for about $300 which I haven't been able to do at home.

Frustrating to spend $500 on parts that I can't install only to hear the [censored] rattling every time I drive it and see the light come back every month or so.
 
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