Catalytic Converter question, oh wise ones...

I have a 2005 Tundra Access cab, V6 auto trans. After 420,000 miles codes are sporadically tripping noting "Bank 1 and Bank 2" catalytic converters. Sometimes 1 or the other and sometimes both, after being reset. Both sides have 2 cat converters, in 2 pieces each. one attached to the manifold and one a separate pipe before the "Y".
Exhaust pipes from the "Y" back need replacing. Trying to order new system. Both "Walker" and NAPA don't list the secondary converter, for a V6, but do list them for the V8.
I know before I ask, but I'll ask anyways. Does anyone know if the V8 secondary converters will fit on the V6?? They look the same, BUT???
Does anyone have a source for the secondary converters??

 

What codes?

If P0430 / P0420, then that's covered over here, search the first page for "430" or "420" to learn more about why it may not be what most will tell you it is (i.e. not the cats)

These trucks in fact do not have two cats (per bank). They have one cat, and a resonator (per bank) on the V8 trucks.

Before you order cats, know what the fuck you're doing. And know about the issues these trucks have, and what brands of cats work. But before you drop the coin, you need to understand that, with these trucks in particular, bad cat codes are often NOT the cats!

You're going to get raped if you buy from NAPA or other local auto parts stores. We can get you parts waaaaay cheaper.

But in general, stick with Denso brand on the AFR/O2 sensors, don't buy from scAmazon or fleaBay. And with cats ... read that thread.

 

Installing new Denso o2 sensors. I noted that the flanges between the left resonator and the "y" pipe are rusted away (dissolved) and appear to be leaking. Any idea where I can purchaser replacements for the left resonator and "y" pipe?? Again for a 2005 Tundra SR5 Access cab, V6 4.0l auto trans.

 

Yes, there's a sticky thread for that, follow the first couple of bullet points: https://www.tundras.com/threads/howto-use-the-toyota-parts-system-to-find-order-parts.113808/

The diagram you're looking for will be under: Engine, fuel system & tools section, under the Exhaust pipe subsection (after you input your VIN into the search box and start the search)

 

Wait, what?? I did not know this. So when I replaced all of these parts, I replaced the cat too???


Shit. Maybe that’s why it was so expensive.

 

No, that's a y-pipe with the resonator, and a muffler.

And I just realized my words were confusing. These cats do not have two cats per bank. I only put the 'per bank' at the end. So I'll update that.

 

Do you mean like this?



I went to my local muffler guy and he fabbed up a replacement.

 

YES! Had I known you were going to come by to take that picture of my truck, you could have helped changing the o2 sensors. LOL! And it's the only connection with a bad flange. Thanks for the input. I'll find a local fabricator that can help.