After market Cat for 98 Gen 2.5 Monty

OneTime

Adventurer
My truck is throwing a CEL code of P0421 which I have determined is coming from the #1 pre cat. Does anyone know of a good after market brand? The OEM is pretty pricey.
 

scrubber3

Not really here
Call Brown's recycling. They take the OEM cores that have been used up and make them new again. They are normally a fraction of what the OEMs cost.

BROWN RECYCLING-(800) 367 9271 See if Cotton still works there.(don't need to but you can if you feel like it) They are located in Alabama and I used them several times when I was still turning wrenches as a profession.
 

OneTime

Adventurer
I thougt there was just one front (pre cat). Does the gen 2.5 have a left and right front cat? If so ho do I find out which one is bad?
 

scrubber3

Not really here
I will check mine tomorrow just to be sure (assuming they could be the same. but I doubt it), but if it has a pre-cat, there will be one for each bank. So` there should be two. I assume that the code says cat efficiency bank 1 correct? Bank one is where the firing order starts. So firing order #1 will be considered as bank one. When you order your cat, they will ask which bank. You should just simply have to answer bank one. Have you considered the possibility of a bad O2 sensor? Behind that catalytic converter? If one of those go bad it will produce a CEL as the one you are reading. Are you having any drivability issues?
 

OneTime

Adventurer
Not the 02 sensor. It has been ruled out to the bank 1 passenger side cat. Called Cotton (thanks for the tip) They only deal with shops. My shop is calling to see if they have any in stock.
 
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scrubber3

Not really here
Let me know how it goes..... You can tell your shop that they owe you free installation for your part in finding such a great and inexpensive catalytic converter supplier. Those guys can save a shop and customers a whole lot of money as well as allow a shop to make a killing from installing cats.
 

off-roader

Expedition Leader
Assuming your state emissions aren't crazy like California's, a smog/exhaust shop may be able to fit a universal aftermarket unit in place. Only problem is, most universals don't last as long as the OEM models which means in a few years, you'll need to replace it again. However in some states like California, they've or they are enacting regulations that require aftermarket equivalents to be equal or greater quality than the OEM cat's.
 

OneTime

Adventurer
Off Roader, you bring up another question. Im in AZ but the truck is from CA. I couldnt find a winter package 98 here in AZ. Plus it was an excuse to go back home and see freinds and family when I went to So Cal for the truck. Most of the aftermarket cats I found on line would not ship to CA, due to the issue you brought up. My question is if a use and after market cat, is that going to cause a problem since its a CA emissions veh?
 

Smksignals

Explorer
Check with a local muffler shop. They can cut the old one out and weld in an approved universal in its place.
 

scrubber3

Not really here
In my experience, universals don't fair so well for pre-cat applications. For installation reasons and the fact that they are not efficient enough. The labor involved can quickly overcome any savings to the part. Factor this into the fact that it may not "fix" the CEL and you've got double the labor. I.E. a big headache for you and the shop. Just my 2 pennies.

Did your shop ever get back to you on price?
 

OneTime

Adventurer
Scub, not yet. I found a muffler shop that will but a after market in for a fair price ($400 P&L). But now you have me worried it wont clear the code out.
 

off-roader

Expedition Leader
Scub, not yet. I found a muffler shop that will but a after market in for a fair price ($400 P&L). But now you have me worried it wont clear the code out.

the point of the replacement cat is to clear the code. If they put one in that doesn't do it, then I think they're the ones who will eat the cost, not you.

The big problem I heard with aftermarket cat's is the way they're made. There are a lot of precious metals used in a Cat which are very expensive. Aftermarket cat's can skimp on the amount used. It will work well enough when new but won't last as long as a properly made one. It will however pass emissions while it's still functioning.

If you have this done by an exhaust shop in CA, I believe a law was recently passed (or maybe it's still being signed/approved) that says they have to use aftermarket cat's that are as good as the OEM cats. Here's a CARB web page where you can find the current list of approved aftermarket cat's... https://ssl.arb.ca.gov/PartsSearchTool/CatalystSearchTool.aspx

If you plan to register your car in California use a CARB approved cat (aftermarket one or OEM one). Otherwise, it use what the state you're in requires.

As for cost... I had mine on an 89 v6 Montero replaced a couple of years back. IIRC, it was ~$175 to install a universal unit and ~$800 to just purchase an OEM unit (installation extra). You need to check the current price since my memory on this isn't 100% certain but I know it was vastly more expensive for an OEM unit.
 

off-roader

Expedition Leader
Correction, I just double checked. It was $225 to replace my cat in my old 90 v6 (not my 89). That included welding the original flanges from the stock cat to the new cat so it would remain a bolt up replacement.

Note... this was back in April 2005.
 

OneTime

Adventurer
Right now plan A is to continue to drive the truck and see if the CEL stays off. If so emmsion test the truck. If the light comes back on my shop is going to pull the cat, ship it to Alabama and have it rebuilt. The truck will be down about a week. But it will cost have that of a new oem cat and should avoid any incompatibility issue of using an after market universal cat.
 

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