A question about UOAs, ZDDP, and cats

[Bryanccfshr]

Originally Posted By: sunfire
Originally Posted By: Robotaz
Originally Posted By: sunfire
Use Red Line's racing oils. They are not bound by API ZDDP levels. And have low NOACK which should help with cat contamination.


Either my original post made no sense at all, or you guys aren't reading everything that I said.

You say to use RL racing oil, which has almost double the phosphorus of the regular. I'm not wanting more, I'm wanting to know if the regular will harm the cat. If the consensus is that I could get myself into trouble harming the cat then I will switch to an API oil. If I need to do that, I am asking which is the best(which I know is a subjective opinion)? I'm wondering if maybe the best strategy would be to just drive it with RL until I notice any oil burn, which could be a very long time, and then back off the ZDDP oil and switch to API oils.


The API ZDDP limits are there for old and new engines that consume large amounts of oil that ultimately make its way into the cat. If your engine doesn't consume oil then use whatever you like.


Actually phosporous is volatized in the crankcase and sucked into the exhaust via the crankcase ventilation. Consumption is not the primary cause of phosporous getting to the catalytic converters. Phosporous volatility is the issue. Most of which flashes into the exhaust reallly soon after an oil change. THat is one of the reasons lower volatility ZDDP is being developed.



to the OP
THe tribological film does not get any thicker or thinner based on PPM, at a certain point it simply becomes inadequate. More ZDDP just means a larger pool of material for the tribofilm.

 

[Robotaz]

Originally Posted By: Bryanccfshr
Originally Posted By: sunfire
Originally Posted By: Robotaz
Originally Posted By: sunfire
Use Red Line's racing oils. They are not bound by API ZDDP levels. And have low NOACK which should help with cat contamination.


Either my original post made no sense at all, or you guys aren't reading everything that I said.

You say to use RL racing oil, which has almost double the phosphorus of the regular. I'm not wanting more, I'm wanting to know if the regular will harm the cat. If the consensus is that I could get myself into trouble harming the cat then I will switch to an API oil. If I need to do that, I am asking which is the best(which I know is a subjective opinion)? I'm wondering if maybe the best strategy would be to just drive it with RL until I notice any oil burn, which could be a very long time, and then back off the ZDDP oil and switch to API oils.


The API ZDDP limits are there for old and new engines that consume large amounts of oil that ultimately make its way into the cat. If your engine doesn't consume oil then use whatever you like.


Actually phosporous is volatized in the crankcase and sucked into the exhaust via the crankcase ventilation. Consumption is not the primary cause of phosporous getting to the catalytic converters. Phosporous volatility is the issue. Most of which flashes into the exhaust reallly soon after an oil change. THat is one of the reasons lower volatility ZDDP is being developed.



to the OP
THe tribological film does not get any thicker or thinner based on PPM, at a certain point it simply becomes inadequate. More ZDDP just means a larger pool of material for the tribofilm.


Wow, this is the kind of info I'm looking for! So does the film become inadequate with lower ZDDP levels as a function of time, friction,or what? thanks.

 

[Bryanccfshr]

Friction. The lower levels provide an adequate film(especcially in low friction engines) every rubbing point and event(revolution for example) is going to consume the active zddp reserves. After time and use here is still zddp in the oil but after so many cycles it is no longer forming films as well as when new. This is one of the parts of the alogorythm GM uses to calculate the OCI of a vehicle with the oil life monitor. This is also a reason why newer engines with rollerized (low fricction)valvetrains can go longer OCI's with less zddp. There are simply less rubbing events per revolution.

 

[Gary Allan]

Originally Posted By: Robotaz

Wow, this is the kind of info I'm looking for! So does the film become inadequate with lower ZDDP levels as a function of time, friction,or what? thanks.



Here's an informative discussion on the GM Oil Life Monitor that will tell you much about ZDDP decay ..which is what the OLM is based on.

http://cgi.ebay.com/ebaymotors/87-93-mus...sQ5fAccessories


But all the contemporary movement toward lower phosphorous oils being a given, there's no reason to think that older (higher) phos levels will have any more impact than they did (NOT) over the life span of the vehicle.

While I can't prove it, this has to be policy and not much from a true substance standpoint. Someone changing their oil too soon can be passing more zddp through their engine than someone with higher zddp level oils who changes it at more reasonable intervals. I firmly believe that this is a time weighted average like most things. 2 tablets of regular strength Tylenol vs. 1 tablet of Xtra-Strength Tylenol.

That (EVEN) said, I've seen about 3 cats go bad in 30 years. Well over multiples of the OEM warranty. Sure, some designs had issues ..but in general, a failed cat is rare.

The current standards cannot be for the rolling fleet's sake of cat protection. It's not been out long enough to be effective to that level. This will benefit the future rolling fleet in either the ability to adhere to stricter cat efficiency standards, or maintain the same standards with smaller catalysts.

3k/3m with high zddp oils? 5k ..10k?

3k/3m with lower zddp oils 5k ...10k?

Less overall cat poisoning.

 

[Bryanccfshr]

Wrong link Gary

 

[Robotaz]

Originally Posted By: Gary Allan
Originally Posted By: Robotaz

Wow, this is the kind of info I'm looking for! So does the film become inadequate with lower ZDDP levels as a function of time, friction,or what? thanks.



Here's an informative discussion on the GM Oil Life Monitor that will tell you much about ZDDP decay ..which is what the OLM is based on.

http://cgi.ebay.com/ebaymotors/87-93-mus...sQ5fAccessories


But all the contemporary movement toward lower phosphorous oils being a given, there's no reason to think that older (higher) phos levels will have any more impact than they did (NOT) over the life span of the vehicle.

While I can't prove it, this has to be policy and not much from a true substance standpoint. Someone changing their oil too soon can be passing more zddp through their engine than someone with higher zddp level oils who changes it at more reasonable intervals. I firmly believe that this is a time weighted average like most things. 2 tablets of regular strength Tylenol vs. 1 tablet of Xtra-Strength Tylenol.

That (EVEN) said, I've seen about 3 cats go bad in 30 years. Well over multiples of the OEM warranty. Sure, some designs had issues ..but in general, a failed cat is rare.

The current standards cannot be for the rolling fleet's sake of cat protection. It's not been out long enough to be effective to that level. This will benefit the future rolling fleet in either the ability to adhere to stricter cat efficiency standards, or maintain the same standards with smaller catalysts.

3k/3m with high zddp oils? 5k ..10k?

3k/3m with lower zddp oils 5k ...10k?

Less overall cat poisoning.


That last paragraph is smart thinking. I agree completely that the changes in oil standards would not be realized on a hardware level yet. I feel a lot better. But, I don't follow what you're saying about the less cat poisoning numbers. Sorry.

 

[bruce381]

Does this layer wear down due to time or friction if you switch to a very low ZDDP oil?

No as long as ZDDP is >1,000 ppm
just stick with RL and spend your time hanging out

 

[StevieC]

The crazy thing is... If ZDDP and other CAT-poisonous additives were higher to begin with the engine wouldn't wear as quickly and start consuming oil. So in effect it would prevent CAT-Deterioration from the prevention of wear which leads to oil consumption.

The problem is they don't want these same oils on the shelves for people that have existing problems where oil consumption is a problem as these people would be feeding all these poisonous additives to the converter and causing decreased catalyst efficiency and in effect more pollution.

I ran a API certified oil for my warranty (So I didn't have a headache in the event I needed to make a warranty claim), then I switched to a non-API certified oil (AMSOIL Signature Series/ASL) and have never looked back.

It's been over 100K KM (60K miles) and the engine still isn't using any oil, and runs like a fine swiss watch.

My car blows 0's on the emission testing machine too, couldn't ask for better results...

 

[Gary Allan]

Originally Posted By: Bryanccfshr
Wrong link Gary


Oooops!!!

https://bobistheoilguy.com/forums/threads/zdp-depletion-and-gm-oil-life-monitor.9644/

 

[Gary Allan]

Quote:
But, I don't follow what you're saying about the less cat poisoning numbers. Sorry.


25,000 people eating various levels of trans fats. Some are gluttons ..some are nibblers.

25,000 people eating various levels of reduced availability on trans fats.

Some are gluttons ..some are nibblers.

25,000 people, on average, will be subject to lessened effects of trans fats.

 

[AzFireGuy79]

FWIW I have been using Redline for around 15 years. I have never had any emissions failures or any other problems for that matter. IF you are looking for ZDDP and POE, look no further than RL. Just stick with it and you will be happy. Might have a little less money for beer though!

 

[johnbottilaw]

Originally Posted By: Robotaz
So I am a big Redline fan, but I've recently become more educated on the ZDDP/catalytic converter issue from using oils that aren't API certified. So the obvious question is: what oils have the best used oil analysis that are API certified? I really don't care whether the catalytic converter works or not because I don't have inspections here, but I am worried that somehow the warranty issue might come back to haunt me if CELs start coming on or something. I'm using Redline 5W-20 in a 2009 Duratec 2.0 with 1,800 miles and a 2009 Mazda MZR 2.3 with about 6,000 miles on it. I am assuming that the best API-certified oil is probably going to be XL-7500. Any advice from the BITOG gurus would be greatly appreciated. Thanks!

-Rob


You are kidding right, this thread is a joke?

 

[johnbottilaw]

Man you had me going there for a second haha

 

[demarpaint]

Originally Posted By: AzFireGuy79
FWIW I have been using Redline for around 15 years. I have never had any emissions failures or any other problems for that matter. IF you are looking for ZDDP and POE, look no further than RL. Just stick with it and you will be happy. Might have a little less money for beer though!

Real world applications vs what a lab will say about ZDDP damaging a cat converter will cause people to question things. Yes in theory ZDDP will ruin a cat converter. In a properly functioning engine I think you have very little to be concerned with. Here is some real world testimony. If your car is an oil burner that is another story.

 

[Robotaz]

Thanks everyone for the replies.

 

[SHAMUS]

RL racing oils have very little detergents; not a good idea in a street car someone is going to keep.

 

[BuickGN]

Originally Posted By: SHAMUS
RL racing oils have very little detergents; not a good idea in a street car someone is going to keep.


You mean RL's racing line, not their street line, right?