Danger Levels of ZDDP?

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Within today's modern catalytic converters what are the limits of ZDDP within today's oils that will over time damage the function of converters themselves?
 
Not sure what you are asking for here. The systems today are designed to survive the limits of additives that are in modern oils. They are not tested against older specs so their survival cannot be guaranteed. If you use an oil that meets the recommendations of your owners manual then the aftertreatment system will be fine.
 
Above 900 ppm in a 20 weight oil.

Maybe above 1000 in a 30?

1200 in a 40?

1400 in a 50...

But it takes hundreds of thousand miles before ruining it in a normal (low) oil consumption engine.
 
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ILSAC grades have ~ 800 ppm Zinc. I would call this minimum rather than optimum.

But Euro 40 grade A3/B4 oils like Edge & M1 0W40 have ~ 1000 ppm Zinc. These Euro cars, BMW's and Porsche and MB's seem to survive fine on a life of 1000 ppm Zinc oil.
 
The phosphorus will damage the cat even at lower levels if it starts burning, the reduction in API certified oils was a compromise to stretch the life of the convertor past the required federal emissions warranty.
 
The current upper limit on most automobile viscosity grades according to the API is 800 ppm phosphorus. However, like 901Memphis said, any amount is going to damage the cat over time if it is entering the exhaust system. The catalyst doesn't suddenly get effected by phosphorus above 800 ppm and have no reaction below that point. That 800 ppm limit is just an allowable amount that causes slower degradation than higher concentrations.
 
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ILSAC grades have ~ 800 ppm Zinc. I would call this minimum rather than optimum.

But Euro 40 grade A3/B4 oils like Edge & M1 0W40 have ~ 1000 ppm Zinc. These Euro cars, BMW's and Porsche and MB's seem to survive fine on a life of 1000 ppm Zinc oil.


Furthermore, these Euro cars are designed to consume some oil. When I have put on aftermarket cats, it seems the better quality cat, the less prone it is for plugging up or seeing the dreaded 420 code. Even if you use high zinc oils.
 
How many cats do/did you guys see ruined by high zinc regular oils pre 2006? I doubt very many. BUT I see at least 3 flat tappet cam equipped cars (Stock cams and springs) with one or more lobes gone with the current off the shelf motor oils, fully 50 percent of my customers didnt know they had to run special higher zinc oils to prevent cam failures. I wish they had not messed with our oils.
 
Originally Posted By: Miller88
I don't think it matters unless you're burning significant amount of oil


This!
 
Originally Posted By: ShotGun429
How many cats do/did you guys see ruined by high zinc regular oils pre 2006? I doubt very many. BUT I see at least 3 flat tappet cam equipped cars (Stock cams and springs) with one or more lobes gone with the current off the shelf motor oils, fully 50 percent of my customers didnt know they had to run special higher zinc oils to prevent cam failures. I wish they had not messed with our oils.


My 4.0 has been fine throughout all the years of my ownership using SN PHM and now SN Mobil 1 HM and it was doing just fine from all the shop oil changes per the receipts shown to me by the elderly woman who was sole previous, and original, owner.

I guess I should expect my 4.0 to blow up any day now considering it hasn't been using API SL rated oil for the past 13 years?
 
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Originally Posted By: JeepWJ19
Originally Posted By: ShotGun429
How many cats do/did you guys see ruined by high zinc regular oils pre 2006? I doubt very many. BUT I see at least 3 flat tappet cam equipped cars (Stock cams and springs) with one or more lobes gone with the current off the shelf motor oils, fully 50 percent of my customers didnt know they had to run special higher zinc oils to prevent cam failures. I wish they had not messed with our oils.


My 4.0 has been fine throughout all the years of my ownership using SN PHM and now SN Mobil 1 HM and it was doing just fine from all the shop oil changes per the receipts shown to me by the elderly woman who was sole previous, and original, owner.

I guess I should expect my 4.0 to blow up any day now considering it hasn't been using API SL rated oil for the past 13 years?



+1

My Jeep 4.0 has been fine as well. I've owned it for almost 100k miles of its life. I've used mostly Pennzoil products, and it sees high revs often.
 
Originally Posted By: ShotGun429
How many cats do/did you guys see ruined by high zinc regular oils pre 2006? I doubt very many. BUT I see at least 3 flat tappet cam equipped cars (Stock cams and springs) with one or more lobes gone with the current off the shelf motor oils, fully 50 percent of my customers didnt know they had to run special higher zinc oils to prevent cam failures. I wish they had not messed with our oils.


Pickings are getting slim now that's for sure.

I honestly don't believe all the hogwash about oils being backwards compatible with older engines. Sure it will run for a while with that SN oil, but is it the best oil for the engine, and I think the answer is no.
 
Originally Posted By: BigD1
I honestly don't believe all the hogwash about oils being backwards compatible with older engines.

Which engines are you specifically speaking about?
 
Originally Posted By: JeepWJ19
Originally Posted By: ShotGun429
How many cats do/did you guys see ruined by high zinc regular oils pre 2006? I doubt very many. BUT I see at least 3 flat tappet cam equipped cars (Stock cams and springs) with one or more lobes gone with the current off the shelf motor oils, fully 50 percent of my customers didnt know they had to run special higher zinc oils to prevent cam failures. I wish they had not messed with our oils.


My 4.0 has been fine throughout all the years of my ownership using SN PHM and now SN Mobil 1 HM and it was doing just fine from all the shop oil changes per the receipts shown to me by the elderly woman who was sole previous, and original, owner.

I guess I should expect my 4.0 to blow up any day now considering it hasn't been using API SL rated oil for the past 13 years?




Easy there. Noone said your engne is going to 'blow up'. If anything, it will grind to a halt.
 
Originally Posted By: -SyN-
What levels of Zinc/Phosphorus (PPM) are dangerous to today's cats?


Any. But the damage goes up exponentially as the dose goes up. However, this is only a factor if the motor is consuming oil via the combustion process. So if your valve seals and rings are good and the PCV system is working well, it's a non-issue. Engines that leak and weep don't hurt CATS.

So why do you ask?

Fleet operators have been using HDEO's with 1200 PPM for decades with cars and trucks, and their CATS do not die early. They die when the engine starts to fail, but gee whiz, guess what - engine failures will take out CATS no matter what ...

My wife's JAG ate a CAT when it lost a head gasket. Not from oil, but from anti-freeze. It will kill a CAT instantly. Oil takes 100,000 miles ...
 
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