Replacing Passenger Side Cat

[redman4455]

Hi guys, my 08 dodge ram 1500 hemi quad cab is throwing a p0420 code showing my passenger cat is underperforming. Ive had the cel on for a couple months now. I have a two part question.

1) Assuming I've gone through my sensors and spark plugs/wires and replaced them and I still throw a code, how difficult is it to replace the cat and is there a recommendation for a CA qualified cat converter? i want to do this myself as i have the tools and I want to save some money for question 2. I've also tried the laquer thinner technique and that didnt work.

2) Should I just go ahead and replace both cats and the exhaust. She has 97k miles and i figure she's due for a new exhaust anyway. Any suggestions for a mild exhaust note model that includes both cats? i like magnaflow but unfortunately they dont make a single side exit cat back for a quad cab anymore. Not looking for extreme performance here, but an upgrade without a huge expense I'm ok with.

 

[Magnaflow]

Hi Redman, we hope this can help you out with your current situation:

1) We offer 2 replacement catalytic converters for your truck that are CARB certified for use in California: part numbers 545355 and 5451355. These are "universal" style converters that will require cutting and welding to install. We recommend professional installation by a local muffler shop or fabricator. You can find more information on them on our website using the links here:

https://www.magnaflow.com/products/...nt-universal-catalytic-converter?aces=9671314

https://www.magnaflow.com/products/...nt-universal-catalytic-converter?aces=9764670

2) We do not recommend replacing catalytic converter unless they are proven to have failed or have a defect. Changing the exhaust for something aftermarket is ultimately up to you. If you were already at a muffler shop, it would not take much more to have them install one of our universal 18" mufflers at the same time for an improvement in sound!

If there is anything else we can help with, please give us a call at 1-800-990-0905!

 

[Karlsweg]

When I had the dreaded P0420 code, the Cats were shot and the o2 sensors were toast. The previous owner didn’t do any maintenance. And it had a blown motor when I got it. Found all the problems after putting my engine in it .

 

[FaceDeAce]

May I suggest you do a couple things first.

inspect the exhaust manifolds and downpipes. Look for cracked manifold or broken manifold bolts. Either will result in an exhaust leak upstream of the first O2 sensor. Causing fuel ratios to go way off, which then loads the cats and sends the downstream O2 into a fit.

Next is to confirm the O2 sensors are working properly. If they are old (5+yrs), consider replacing them. Same for the MAP sensor.

After those are confirmed if 0420 still ringing then, yes time for a cat replacement.

As for a muffler change. Easy. Cut upstream and downstream of the stock muffler. Weld in a short chunk of pipe and a magnaflow 3”x3” single 18” muffler. Leave the tailpipe as is. Leave the cats and crossover pipes as is. One step up would be to include an improved Y-pipe. The stock one is a pinch point.

Hope that helps!

 

[redman4455]

Guys, I'm sorry I got lazy on this and didnt respond. Thought I wrote a dead thread but looks like I missed out.

Magnaflow, thanks for the part numbers, will definitely want to go Magnaflow if I make changes to the cat or muffler, love a Magnaflow exhaust note! I have a good muffler guy who is an honest Abe so I'm comfortable he will make the right diagnostic and give good advice.

That being said, Karlsweg and FacedeAce thanks for the input. haven't done the work yet so I'll make sure to check the sensors first and hopefully that resolves it. Now that I think of it, I did clean the throttle body about a week or two before the code was thrown... might have something to do with it. Maybe the sensors are screwed? Anyway, thanks guys.