Additives that Clean Catalytic Converters?

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Are there any additives out there that can legitimately clean or lengthen the life of catalytic converters? My Jeep burns oil, and one or both cats had to be replaced at about 76k miles.

I'm now running M1 0w40 to reduce consumption, but it is about 10% higher in phosphorus than regular M1, and even more so than an oil like M1 AFE. I'm just wondering if the higher phosphorus in the 0w40 will shorten the life of the cat, as the engine burns oil, and if so, is there an additive that can "clean" the cat.

I'm not sure if I'd be looking for an oil additive or a fuel additive, if it exists, so I'm posting in both forums.
 
I read somewhere that if you physically removed the cat and dunked it in a bucket of laundry detergent, that might help.

The honeycomb gets coated in goo, and if de-goo'd, it'd be more effective.
 
I need to check the specs on M1 0w40. I'm not sure how its ash content compares to others.

Wow, I thought you were joking about the laundry detergent.

While I'm pretty sure oil consumption killed the first cat, my mechanic said he replaces Chrysler cats early frequently, even with engines that don't burn oil. I'm still assuming the oil consumption did it, or at least accelerated it.

Any additives that can clean enough to prolong its life?
 
A one time E 28 enthusiast had some success with a controlled burn. He took the vacuum off the fuel pressure regulator so it ran a little rich at highway speeds. Then he normalized and gave the car an hour long Italian tune up. My first BMW passed MA emissions at 330 K miles on the original cat. I learned from my Jeeps that replacing the cat without fixing the root cause of the failure is a short term deal.
 
Originally Posted By: IndyFan
I need to check the specs on M1 0w40. I'm not sure how its ash content compares to others.

It's a full blown full SAPS oil with SA content of 1.3%. It has more SA than Rotella T6.
 
Originally Posted By: andyd
A one time E 28 enthusiast had some success with a controlled burn. He took the vacuum off the fuel pressure regulator so it ran a little rich at highway speeds. Then he normalized and gave the car an hour long Italian tune up. My first BMW passed MA emissions at 330 K miles on the original cat. I learned from my Jeeps that replacing the cat without fixing the root cause of the failure is a short term deal.


There's varying theories as to what is happening to the oil. I think it is getting by the rings in a couple of cylinders, which is a common thing in these Jeep 3.8 engines. Until it burns more than 1 quart per 1k miles, Jeep won't do anything about it. (I've got a lifetime powertrain warranty.) These 3.8's are notorious for using oil. My brother ran his Chrysler mini van with this same engine over 225k without ever replacing the cat, which shocks me. His used oil about like mine for nearly its entire life. Mine started consuming at around 40k. It has been pretty consistent since, but burning a little less with the 0w40.

I've tried a bunch of different oils and weights. The only significant difference has been with 5w20, which tends to burn off or be consumed at a higher rate.

Maybe the best thing to do is go with an oil that has the lowest of whatever most contributes to failing cats. I just don't want to give up wear protection for it.
I saw one suggestion for Max Life. Others to consider?

I'm heading to Moab, UT for an off-road trip at the end of the month, so that's another reason I went back to the 0w40 M1. We'll be doing LOTS of low speed crawling in low range.
 
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Originally Posted By: gathermewool
Was the cat replaced for free, under warranty?


Yes. My understanding is that the emissions warranty ends at 100k, and it is not covered under my lifetime powertrain warranty.
 
I've been doing a bit of reading and I'm wondering if I should be running Mobil 1 ESP 5w30. It has low ash, and low phosphorous, to protect the cat. Thoughts?
 
Originally Posted By: IndyFan
I've been doing a bit of reading and I'm wondering if I should be running Mobil 1 ESP 5w30. It has low ash, and low phosphorous, to protect the cat. Thoughts?


That's one of the reason's why they recommend it for diesel apps. It might be a good choice for you.
 
Why he didn't use lacquer thinner to flush the cat? Would probably work much better directly than via gas tank...
 
Originally Posted By: Nebroch
Why he didn't use lacquer thinner to flush the cat? Would probably work much better directly than via gas tank...


I'm guessing it had to be hot. Just a guess, as I know very little about any of this.

Just to clarify for everyone, my cats aren't dirty yet. The new one(s) have only about 13k miles on them. I'm just thinking about what I can do to prolong them, if the failure of the previous one was due to oil burn. I'm not 100% sure of that, but I strongly suspect it.
 
there is a product sold at Peps AZ & AAP--it is called Cat-Clean. 25 bucks a bottle--Peps has a pack of 2 for 25 bucks--I have no idea what is in it or if it works, but the product is out there
 
Originally Posted By: steve20
there is a product sold at Peps AZ & AAP--it is called Cat-Clean. 25 bucks a bottle--Peps has a pack of 2 for 25 bucks--I have no idea what is in it or if it works, but the product is out there


It contains acetone,toluene,xylene and a few other chemicals.

Don't know if it works or not. I'd just mix the 3 chems I mentioned and suck them into a vacuum line.
Should clean the cat.
 
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