2011 Ram 2500 5.7L Poor Performance

[LongTom]

Hello everyone, I recently purchased a 2011 Ram 2500 5.7L 4x4 Crewcab Longbox with I believe 3:73's a few weeks ago. Truck has an engine code (P0420) for catalyst efficiency below threshold on bank 1. Truck feels a little underpowered for 390 HP and If i am absaloutley driving like a grandma at flat, no wind highway speeds, the computer says i am getting 12.5 MPG. Its way worse If im driving regularly. I understand the thing has the aerodynamics of a house and has got a chunky V8 inside, but I feel like It should be running a little nicer. Maybe its normal and these trucks normaly run like that. Could be wrong.

I did not buy the truck for the fuel efficiency, but man.

Recently replaced 02 sensors on bank 1, still no luck with the engine light. Im thinking the cat is not having a good time. Found a shop to cut the cats and add non-fowlers for a good price but am worried that deleting the cats would have some sort of negative impact. Maybe im wrong?

Is this the way to go? If anyone has any information or tips, it would be much appreciated. Thanks.

 

[markabby]

there's a few good cat cleaners out there. I'd look for the best one and try that before sinking $$$ into a new cat.

 

[Wild one]

Hello everyone, I recently purchased a 2011 Ram 2500 5.7L 4x4 Crewcab Longbox with I believe 3:73's a few weeks ago. Truck has an engine code (P0420) for catalyst efficiency below threshold on bank 1. Truck feels a little underpowered for 390 HP and If i am absaloutley driving like a grandma at flat, no wind highway speeds, the computer says i am getting 12.5 MPG. Its way worse If im driving regularly. I understand the thing has the aerodynamics of a house and has got a chunky V8 inside, but I feel like It should be running a little nicer. Maybe its normal and these trucks normaly run like that. Could be wrong.

I did not buy the truck for the fuel efficiency, but man.

Recently replaced 02 sensors on bank 1, still no luck with the engine light. Im thinking the cat is not having a good time. Found a shop to cut the cats and add non-fowlers for a good price but am worried that deleting the cats would have some sort of negative impact. Maybe im wrong?

Is this the way to go? If anyone has any information or tips, it would be much appreciated. Thanks.

I've had good luck with these little guys.I'm not sure how well they'll work on your 2011,but they work good on my 2013 5.7 300C with 6.4 manifolds and no cats.I've put about 6,000 clics on it with these in place and haven't had any cat codes with them in place.What part of Alberta are you in?

https://www.amazon.ca/Stainless-Universal-Catalytic-Converter-Downstream/dp/B07R5SX5XG

I've also used these ones ,i used these ones on my wifes 2019 6.4 Challenger when i cut the cats off it.Ran them for roughly 10,000 clics before i got around to tuning it,and never had any cat codes.

https://www.amazon.ca/MiniCat-Adapter-Stainless-Extension-Extender/dp/B07R5SVDQZ

 

[jws123]

my old 2011 got 13 mpg shutting MDS off helped get lil more mpg because i wasnt constantly hitting gas to speed back up. My 2014 with the 8 speed gets 16 Also do your exhaust manifolds leak at all yet? It will cause a cat code if bad enough.

 

[LongTom]

I've had good luck with these little guys.I'm not sure how well they'll work on your 2011,but they work good on my 2013 5.7 300C with 6.4 manifolds and no cats.I've put about 6,000 clics on it with these in place and haven't had any cat codes with them in place.What part of Alberta are you in?

https://www.amazon.ca/Stainless-Universal-Catalytic-Converter-Downstream/dp/B07R5SX5XG

I've also used these ones ,i used these ones on my wifes 2019 6.4 Challenger when i cut the cats off it.Ran them for roughly 10,000 clics before i got around to tuning it,and never had any cat codes.

https://www.amazon.ca/MiniCat-Adapter-Stainless-Extension-Extender/dp/B07R5SVDQZ

Just outside of Calgary! The shop I found in the city would be able to cut the cats and add non-fowlers to prevent the truck from running terrible. I might have to tell them about using steel wool since apparently it wont work without it!

 

[LongTom]

my old 2011 got 13 mpg shutting MDS off helped get lil more mpg because i wasnt constantly hitting gas to speed back up. My 2014 with the 8 speed gets 16 Also do your exhaust manifolds leak at all yet? It will cause a cat code if bad enough.

Nothing out of the ordinary. Might go have a look in the morning to see if I can find any small leaks because there is nothing big! And is your truck a 1500? Because I don't believe the 2500 5.7's had MDS.

 

[jws123]

Nothing out of the ordinary. Might go have a look in the morning to see if I can find any small leaks because there is nothing big! And is your truck a 1500? Because I don't believe the 2500 5.7's had MDS.

My bad didnt realize yours was a 2500 no mds.

 

[Wild one]

Just outside of Calgary! The shop I found in the city would be able to cut the cats and add non-fowlers to prevent the truck from running terrible. I might have to tell them about using steel wool since apparently it wont work without it!

I've done the drilled out/stacked anti-foulers with steel wool,on some it works,some it doesn't.The benefits of the anti-foulers is you can usually find them at Napa / Canadian Tire etc.The only place i've found the mini cats is on amazon

 

[Wild one]

Just outside of Calgary! The shop I found in the city would be able to cut the cats and add non-fowlers to prevent the truck from running terrible. I might have to tell them about using steel wool since apparently it wont work without it!

If the anti-foulers don't pan out,i have a brand new set of these,i'd sell,in Airdrie.

https://www.amazon.ca/Stainless-Oxygen-Sensor-Catalytic-Converter/dp/B07Y8DM7L4?pd_rd_w=0AkxG&content-id=amzn1.sym.453d958b-c1a6-43c5-9e87-411298fe30c2&pf_rd_p=453d958b-c1a6-43c5-9e87-411298fe30c2&pf_rd_r=EVH2QGW4Y7WQRSAFAE28&pd_rd_wg=zj6xx&pd_rd_r=700a1bf7-7ea7-4472-be29-57c0850896cd&psc=1&ref_=pd_bap_d_csi_day0_0_i

 

[LongTom]

If the anti-foulers don't pan out,i have a brand new set of these,i'd sell,in Airdrie.

https://www.amazon.ca/Stainless-Oxygen-Sensor-Catalytic-Converter/dp/B07Y8DM7L4?pd_rd_w=0AkxG&content-id=amzn1.sym.453d958b-c1a6-43c5-9e87-411298fe30c2&pf_rd_p=453d958b-c1a6-43c5-9e87-411298fe30c2&pf_rd_r=EVH2QGW4Y7WQRSAFAE28&pd_rd_wg=zj6xx&pd_rd_r=700a1bf7-7ea7-4472-be29-57c0850896cd&psc=1&ref_=pd_bap_d_csi_day0_0_i

That would be awesome! Trucks getting the cats chopped off tomorrow. Exhaust shop also said that the foulers were a 50/50 shot. If they dont work, I can definitely swing on by. Have you found these type of spacers to work?

 

[Wild one]

That would be awesome! Trucks getting the cats chopped off tomorrow. Exhaust shop also said that the foulers were a 50/50 shot. If they dont work, I can definitely swing on by. Have you found these type of spacers to work?

I haven't tried the 90 degree versions out yet.I bought those 2 and these 2 for my 5.7 300C when i swapped it to the 6.4 manifolds and catless mids off my wifes 6.4 Challenger,as i wasn't sure which one i'd need,and the first ones i stuck in it,were the straight versions,and they took care of the cat codes,that i was getting with the old double stacked/stuffed with steel wool normal hollow anti-fouler trick ,so i never used the 90 degree versions.

These are the ones that i'm using in the 300,but they're basically identical,with-out the 90

https://www.amazon.ca/Stainless-Universal-Catalytic-Converter-Downstream/dp/B07R5SX5XG