Hello all, I need some help here. I am having the hardest time finding a catalytic converter for this truck, or even the correct exhaust system layout for it. All of the layouts show that I Have two ( left and right Sid ) converters. this is not the case for my truck. My truck has one cat, that is two in and one out. with two O2 sensors ( up and down stream ). Does anyone have any info on why mine is different?

 

California has stricter emissions and if the truck was originally sold for the California market, it likely came with a dual converter setup to help meet CA emissions standards. Sounds like you have a "Federal" truck which meets emissions for the other 49 states.

I'd suggest downloading the 2001 Dodge truck parts manual to see if you can find the OEM part number for your converter and try searching on that.. You can find the factory parts manual downloads here - https://dodgeforum.com/forum/2nd-gen...s-manuals.html

 

When I look at the part manual for my truck, the second it goes to the 8.0L engine it shows two catalytic converters! lol, this is so frustrating!

 

As you've stated, it looks like the exhaust you have for the V10 is harder to source OE style parts. You may have to end up running dual cats due to parts availability.

 

The other oddball on the one V10 I've worked on is the exhaust anchors to the t-case kinda under the driver seat.

People will say they don't know why the NP241D has threaded studs holding the case halves together on the left. It's for exhaust brackets.

Unfortunately, as to the ACTUAL question about the number of cats, I'm no help. Here's a bump for you

 

I would suspect that it isn't stock..... The 5.9 had a two into one cat..... and the V-10 was based on the 5.9.... Wonder if one of the magnaflow fellers for a 5.9 would bolt up?

 

The factory parts list shows 2 cats (52103078AH) for federal emissions and one cat (52103201AC) for California emissions. That makes sense because the CA trucks have an additional pair of O2 sensors right before and after the cat to monitor efficiency. The OP truck is likely CA emissions. Walker claims to have a proper replacement:

 

The Walker replacement cat looks like a part number 81512. Lots of places seem to carry it. It has 2 two inch inlets and one 2.5" outlet. It has one port for the upstream O2 sensor. The downstream O2 sensor would require a bung in the pipe behind the converter to accommodate the 2nd O2 sensor. This sounds like it should work for your needs based upon your description.

Curious as to whether or not you're the original owner of the truck and whether or not it was made for the California environment or Federal (legal for the other 49 states)? I ask, as the CA trucks tended to have 4 O2 sensors..

 

My thoughts are, somehow this truck is 49 state truck and made it into the California system (OP states California as residence) without being upgraded/updated to CARB specs. I am completely unfamiliar with how California system works other then they have much stronger and strongly enforced emissions regulations. I would assume this trucks carb stamp or lack of one would've raised a flag at the registration office. I remember when I worked at the truck shop, heavy trucks looking to get CARB emissions inspection stamps we had to go through and turn on certain parameters in the ECM. Being its a 49 state truck it has one cat, but living in California they auto stores can only sell CARB level replacement parts so the 49 state one doesn't come up. The other though is it was converted at some point but seems like a lot of work to still have a cat, there is really no benefit to the swap, just work.

 

The heavy duty 5.9's had duel cats along with the V10. Not sue if this is the case for all years and CA adds to it. I would look for all the 02 plugs(used or not) that may give you and idea of what it came with.