ZDDP level change after oil analysis

[kschachn]

Hmm sure. Where did you learn what constitutes proper testing? And how are you evaluating the outcome? You haven't really explained what is a better test of wear than what I noted.

Exercises in science are statistically valid unlike personal testimonials of unknown operators using various engines of unknown health under completely uncontrolled operating conditions and evaluated by personally influenced and determined means.

 

[HandOverFist]

This has nothing to do with test procedures...it has everything to do with making a informed decision on ZDDP levels required. I have seen nothing to answer that question definitively. Not attacking science here lol...

 

[kschachn]

In most engines it has everything to do with spring pressure. Even true flat tappet engines only require elevated levels of ZDDP during break-in, otherwise unless you are running high spring pressure then the amount in an API SP oil is sufficient.

Which has been shown by the scientific tests in SAE J300 by the way.

 

[HandOverFist]

And these tests specifically address the amounts required? The reason I ask is one hears/sees these figures bounced around like gospel, but one is never provided scientific findings to justify those numbers. Even in this thread it was suggested that up to 1500ppm ZDDP was needed in certain circumstances. What or where were these numbers derived from? I'm not arguing that certain amounts of ZDDP are not required for specific instances, merely questioning how those numbers came to be.

 

[kschachn]

And these tests specifically address the amounts required? The reason I ask is one hears/sees these figures bounced around like gospel, but one is never provided scientific findings to justify those numbers. Even in this thread it was suggested that up to 1500ppm ZDDP was needed in certain circumstances. What or where were these numbers derived from? I'm not arguing that certain amounts of ZDDP are not required for specific instances, merely questioning how those numbers came to be.

I guess I'm a bit surprised you wouldn't know the answer to that given your posts here.

 

[HandOverFist]

Maybe someone else can answer the question then? That would be assuming there is a credible answer...even folklore has an origin.

 

[RDY4WAR]

What you're asking is subjective and very engine and application specific. You can't expect every person to learn and understand lubricant chemistry and tribology to the point of discerning different types and concentrations of ZDDP for their specific application nor can you expect someone qualified to teach such to each individual person. That's part of why certs and approvals exist is to remove that questioning and provide a standard, and I say that as someone who doesn't care about approvals. (For a different reason)

There's more factors to wear protection than just ZDDP. Many other additives affect wear as well as affect ZDDP's behavior through synergistic or conflicting chemistry. What you're asking for is something even PhDs with 40 years in the field are still testing and researching to this day with an entire tribological society dedicated to studying it.

The best thing is to focus on what an oil does rather than what an oil is.

 

[HandOverFist]

With that said then I have no other conclusion to reach is other than there is no concrete source that anyone can use or refer to in order to make a intelligent choice. It would seem that most are simply using word of mouth and various claims to select specific oils. It is no wonder then that many still pour ZDDP additives into existing oils or use diesel oils in gasoline engines...simply for the sake of ZDDP.

 

[RDY4WAR]

That's not what I'm saying. I'm saying that you're asking for static figures for a dynamic target. I can't give you a 1 liner that sums up everything anybody needs to know about ZDDP. It's just not that simple. You can't summarize it in 1 white paper or even 1 book. Les Rudnick's books have 100+ pages mentioning ZDDP. It's just too vast of a topic.

Many times people have tried to dumb it down for the layman to grasp. However, the topic is so complex, and requires a certain level of understanding of chemistry, that attempts to dumb it down often end up oversimplifying and creating falsehoods from misinterpretations of the oversimplifications. This is true for lubricants in general. Take the whole multiple sized balls vs same sized balls for the conventional vs synthetic comparison as a prime example of that.

The data is out there, and it's constantly evolving as new discoveries and advancements are made. The problem is getting people to actually read it and understand it. The overwhelming vast majority of people want to be spoon fed a 1 line response that tells them all they need to know, and it's just not possible. That's why standards like API set a minimum for phosphorus and why classic/hot rod and racing oils use more ZDDP than most will need. It's better for business and one's sanity to do it that way rather than trying to educate and argue with someone who doesn't even know what elements are in ZDDP, much less how it works.

 

[HandOverFist]

The reason I asked the question specifically in the manner I did was if elevated ZDDP content is warranted then one would logically assume you would see a significant decrease of that particular content in used oil analysis reports. I have yet to see this born out. If this is something that cannot be reliably tested, then we truly are in the dark.

I do understand there are more components added to modern oils to counter the reduced ZDDP levels currently used...just trying to keep this on a simple level for this discussion. Perhaps if some here that are using high ZDDP level oils could chime in with their analysis results?

 

[SuperSalad]

But it's already been pointed out that there is no test to quantify the amount of ZDDP in oil, so how would one see a decrease in a UOA?

The test looks at zinc and phosphorous, which one might assume are from ZDDP, but neither of them will be removed from the system during use. So the contents should be relatively the same from start to finish barring dilution and other normal ways oil is altered during use.

I'm not sure what you are implying we are in the dark about.

 

[RDY4WAR]

For a comparison here, let's look at 2 different ZDDPs and blend them in a base oil.

ZDDP 1

Zn - 9%
P - 8.5%
S - 17%

ZDDP 2

Zn - 10.5%
P - 9.5%
S - 19%

ZDDP 1 + Base Oil (Blend 1)

Concentration = 0.94%
Zn - 846 ppm
P - 800 ppm
S - 1598 ppm

ZDDP 2 + Base oil (Blend 2)

Concentration = 0.84%
Zn - 882 ppm
P - 800 ppm
S - 1596 ppm

Which oil blend has more ZDDP?

Now pretend we don't know the elemental content of the 2 ZDDPs nor the blending concentration. Which oil blend has more ZDDP?

So many people in the hot rod world would look at 882 ppm vs 846 ppm Zn and say "Oh, oil 2 must be better. It has more zinc!" You see the problem? Many wouldn't even acknowledge the phosphorus and sulfur, much less acknowledge that they're the anti-wear elements here and not the zinc. In fact, many would laugh at you like you're the idiot if you try to tell them that.

BTW, ZDDP 1 is a blended primary/secondary alkyl ZDDP and ZDDP 2 is all primary alkyl, making ZDDP 2 even less desirable from a wear protection standpoint.

 

[HandOverFist]

But it's already been pointed out that there is no test to quantify the amount of ZDDP in oil, so how would one see a decrease in a UOA?

The test looks at zinc and phosphorous, which one might assume are from ZDDP, but neither of them will be removed from the system during use. So the contents should be relatively the same from start to finish barring dilution and other normal ways oil is altered during use.

I'm not sure what you are implying we are in the dark about.

If there is no test to quantify the amount of ZDDP in oil, then how does one qualify a specific ppm number as being superior over another? Surely you can see the mystery involved here. ZDDP is supposedly a sacrificial property...are you saying it is impossible to gauge it's depletion?

 

[SuperSalad]

If there is no test to quantify the amount of ZDDP in oil, then how does one qualify a specific ppm number as being superior over another? Surely you can see the mystery involved here. ZDDP is supposedly a sacrificial property...are you saying it is impossible to gauge it's depletion?

I wouldn't assume to qualify the superiority of one amount to another. Performance is entirely...100% dependent on the oil as a whole, not one single additive.

Performance depletion might give you an indication. Oxidation rate/progression since ZDDP is anti-oxidant, is sometimes used as a gauge.

But concrete and definitive points in time where you can point to a cutoff in ZDDP performance isn't going to happen. Its contribution to performance lessens as the oil ages/is used. The rate or percentage of depletion is not going to be apparent from a single UOA. Maybe if you canvassed a lot of UOAs over a single oil change, you could maybe plot something that is accurate for that specific oil change.

 

[HandOverFist]

It is not myself trying to qualify anything at all...looking for evidence to explain why higher ppm ZDDP are preferred in many instances. Forums such as this one across the country reveal a multitude of people swearing by these high ppm oils, but there seems to be no science to back up their selections. This makes it difficult to plant oneself in the more is better camp of thinking.

"I wouldn't assume to qualify the superiority of one amount to another. Performance is entirely...100% dependent on the oil as a whole, not one single additive." This right here I will completely agree with from my own experience.

 

[SuperSalad]

It is not myself trying to qualify anything at all...looking for evidence to explain why higher ppm ZDDP are preferred in many instances. Forums such as this one across the country reveal a multitude of people swearing by these high ppm oils, but there seems to be no science to back up their selections. This makes it difficult to plant oneself in the more is better camp of thinking.

Well I can't count myself as one in that camp. I have personally tested varying degrees of ZDDP and above the 1600-1800 ppm range is where anti-wear performance typically would drop off and start getting worse than the lower concentrations. When I was formulating, I liked to keep it in the 800 -1200 ppm range to hit the performance marks I was shooting for.

 

[HandOverFist]

Well I can't count myself as one in that camp. I have personally tested varying degrees of ZDDP and above the 1600-1800 ppm range is where anti-wear performance typically would drop off and start getting worse than the lower concentrations. When I was formulating, I liked to keep it in the 800 -1200 ppm range to hit the performance marks I was shooting for.

Yes, that was my impression as well looking at the data thus far. 900 ppm in my current synthetic selection.

 

[kschachn]

It is not myself trying to qualify anything at all...looking for evidence to explain why higher ppm ZDDP are preferred in many instances. Forums such as this one across the country reveal a multitude of people swearing by these high ppm oils, but there seems to be no science to back up their selections. This makes it difficult to plant oneself in the more is better camp of thinking.

It’s not that many on here, save for a few people that tend to not understand other things as either. This and “a slug of boron” or “dose of moly”.

Sometimes the same ones that think they can tease so many things out of a $30 spectrographic analysis of decomposed compounds, and the significance of “wear rates”.

 

[HandOverFist]

That's the conundrum. The search for the reasoning and science (if any exist) behind many people's steadfast selections of oil based on the most part from it's ZDDP content while at the same time completely overlooking the overall package.

 

[SuperSalad]

Preaching to the choir, my friend. Preaching to the choir.