CJ-4 oil for older flat tappet engines..

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I forgot to mention that while the high detergency and dispersency additives in a diesel rated oil can reduce the effectiveness of a ZDDP package vs the package in a gas engine, but it is related to the activation temps of the product. The diesel rated oil reputedly requires a higher activation temp. By how much, I do not know. Is this an issue? I doubt it. Do diesel have substantially higher oil temps than a gasser? Not really. It's more an operational cycle issue, whereby diesels most often are run hard, long and hot versus a higher percentage of gasser are short hopped and seldom reach full oil temp. In theory, a modern, short hopped light truck diesel could run into the same issues... if that's an truly an issue. So while the differences in ZDDP chemistry between a gas and dual rated diesel oil may exist, it seems doubtful it's a significant issue. I see the lack of optimal viscosity choices as more an issue, but it you are willing to get intothe more expensive dual-rate oils, that may not be much of an issue. Especially if you consider that many "classic" or late generation flat tappet engines were spec'ed of 10W30 or 10W40 oils that are esily matched in the HDEO realm.
 
Originally Posted By: Jim Allen
Originally Posted By: Gokhan
For a flat tappet cam gasoline engine with moderate valve spring pressures (such as a flat head engine) the generally accepted minimum level of protection is 1200 to 1300 ppm of Zinc.

Generally accepted by whom? The companies that make specialty oils for "classic" cars and want to steer you away from other, less expensive oils? Or is it from companies that sell ZDDP additives that want to scare us into more ZDDP? Actually, I see you clipped the sales pitch from the Cam-Shield website in your post, in addition to linking to it, and that is not your own writing. I would hardly regard that as an objective source of information.

The less complex truth is the API has backrated many SM and SN oils for flat tappet engines. That may or may not be the whole story, but testing was done to qualify the ratings based on the 800 ppm levels of ZDDP. And remember that their are other additives that do the same thing. I personally think nearer 1000 should be a minimum, no other additives in the picture.

One good clarification point: A purely "diesel rated" oil, e.g. API CI only, is not suitable for any gas engine. That has less to do with ZDDP than other things, however. But when we talk about HDEOs, we are talking about dual rated oils that may be CJ-4/SM or CI-4/SM. They are dual rated for gas or diesel and contain enough for diesels and way more than a low-po flat tappet engine requires unless breaking in a new cam.

FInally, if 1300 is the minimum amount required, how do you account for the fact that many older oils, period to the era of the flat tappet, had nowhere near that much?

I didn't post their article for their claims on ZDDP levels. Sure, they sell ZDDP treatment and they will claim you need more ZDDP.

It's of course true that it's very important to have a good balance between different additives in the oil. Even the article states that. For this reason, when people blend their own oils (mixing different brands or viscosities), I have concerns that the resulting mix may actually be worse than the constituents. I also have concerns against using any kind of aftermarket oil additive.

However, the reason I posted the article is that they make a very good point about diesel-engine oils and racing oils not being the optimum oils for gasoline engines. Their point about detergent levels being too high in diesel-engine oils and too low in racing oils is valid. Their point about diesel engines using different ratios of primary to secondary ZDDP, optimized for diesel engines, is also valid. They also make a good point about different types of viscosity-index improvers used. This is all very useful and true information.

Your point about the CJ-4/SM dual certification misses the mark. While it's true that virtually any CJ-4 oil is dual-certified for SM use, what your point is missing is that CJ-4/SM oils are exempt from some tests and specs of SM. They only meet some of the specs and tests of SM. Quoting from API:

"If API CI-4 and/or CJ-4 categories precede the “S”
category and there is no API Certifi cation Mark, the
Sequence VG (ASTM D6593), Ball Rust (ASTM D6557),
and Gelation Index (ASTM D5133) tests are not required."

"For all viscosity grades: If API CH-4, CI-4 and/or
CJ-4 categories precede the “S” category and there
is no API Certifi cation Mark, the “S” category limits for
phosphorus, sulfur, and the TEOST MHT do not apply.
However, the CJ-4 limits for phosphorus and sulfur do
apply for CJ-4 oils."


The bottom line is that the dual-certified CJ-4/SM oils are not intended for mainstream gasoline-engine use. They are intended for some fleet use, where the fleet operators may find it more convenient to use a single type of oil.

CJ-4/SM oils are not optimized for gasoline engines, and the article helps explain it why, and the API reference I quoted officially tells you that they are not optimized for gasoline engines.

My recommendation once again is Mobil 1 0W-40 SN without any aftermarket additives. Any other high-quality xW-40 SN or xW-50 SN oil with good ZDDP and moly levels intended primarily for gasoline engines will also work well. Do not use xW-30 or thinner, as they don't provide as good boundary lubrication because of thinner oil film. Also, remember that only the "Resource Conserving" SN oils have a maximum limit on ZDDP but all CJ-4 oils have a maximum limit of 1200 ppm P on ZDDP. In addition, the type of ZDDP used in SN-only (gasoline-engine) oils is a more potent antiwear additive in gasoline engines than the type of ZDDP used in CJ-4 (heavy-duty-diesel-engine) oils.
 
Hi,
Gokhan - Sorry to intrude again but many iterations from you in this Thread (and some others) fly in the face of reality!

For various reasons I have used HDEOs in petrol engines since the late 1950s - I may say and ALL with excellent end results. So have many Fleet Owners with millions of $ tied up in assets - they typically have great results too

Ensuring that the correct API/ACEA/Manufacturer requirements are met is always paramount to long life and durability on the way

Of course like any other contributor your input is welcome no doubt, but re-reading some of your own rhetoric may assist your understanding of the subject.

Experience plays a great part when making statements here on BITOG - at least!
 
Originally Posted By: Doug Hillary
Hi,
Gokhan - Sorry to intrude again but many iterations from you in this Thread (and some others) fly in the face of reality!

For various reasons I have used HDEOs in petrol engines since the late 1950s - I may say and ALL with excellent end results. So have many Fleet Owners with millions of $ tied up in assets - they typically have great results too

Ensuring that the correct API/ACEA/Manufacturer requirements are met is always paramount to long life and durability on the way

Of course like any other contributor your input is welcome no doubt, but re-reading some of your own rhetoric may assist your understanding of the subject.

Experience plays a great part when making statements here on BITOG - at least!

Doug, we're not saying here that a CJ-4/SM oil wouldn't work in a gasoline engine. That would be ridiculous. If that's how you read my posts, you're mistaken. I myself used CJ-4 15W-40 in my car for many years with very good results.

Regarding the "certification" of dual-certified (CJ-4/SM) oils, even API states that these oils may not be optimal for gasoline engines, as they don't meet every requirement of an SM-only or SN-only oil.

The point is that an SN-only oil is better optimized for a gasoline engine and there is really no benefit of using a CJ-4 oil in a gasoline engine. You don't need the high concentration of soot dispersants of a CJ-4 oil in a gasoline engine. Too much dispersants strip the antiwear additives away, which is not good for this user's flat-tappet application. I suggested Mobil 1 0W-40 SN with 1000 ppm P, which is the same as the typical ZDDP concentration in a CJ-4 oil. He can also use something like a Pennzoil Yellow Bottle 10W-40 SN, which has about 850 ppm P, and save a lot of money, given the chances that his engine uses a lot of oil.
 
I agree that dual rated HDEOs may not be optimal for all engines but I submit they can be optimal or nearly so for older flat tappet engines when measured against the older specifications they were originally certified under. Flat tappet engines were largely gone by the mid 1990s, so they would have operated under a lower oil spec than today's oils can offer. It doesn't take much to beat those old oils with the array of lubricant available today, up to and including HDEOs.

The fact that HDEOs are exempt from certain API gas oil tests (likely because there is a higher or different standard for a similar test in the CJ certification) is no condemnation in and of itself.

As to the diesel primary vs secondary ZDDP ratios being different than a gas formulation, it's a point but I'm not convinced it's particularly noteworthy one in the grand scheme of things. If you are only talking about "perfect world" stuff, I'll concede the point. If we are talking about general viability of HDEOs within the context of an ordinary engine, nothing I have seen would indicate a measureable difference on any level you'd care to mention, even a long ways down the road. As Doug mentioned, there has been a whole lot of practical evidence aquared that HDEOs work fine in gas engines. There are many fleets that have used HDEOs for millions of miles in their gas fleets that delivered perfectly acceptable performance.

I don't disagree that the oils you recommended are fine oils and suitable for the purpose (we could argue about your viscosity recommendations... ( : < ), I think that HDEOs are more a viable alternative than you seem to want to admit.

Also, you never commented on the old oil VOAs and the apparent low levels of ZDDP.
 
Originally Posted By: Jim Allen
I forgot to mention that while the high detergency and dispersency additives in a diesel rated oil can reduce the effectiveness of a ZDDP package vs the package in a gas engine, but it is related to the activation temps of the product. The diesel rated oil reputedly requires a higher activation temp. By how much, I do not know. Is this an issue? I doubt it. Do diesel have substantially higher oil temps than a gasser? Not really. It's more an operational cycle issue, whereby diesels most often are run hard, long and hot versus a higher percentage of gasser are short hopped and seldom reach full oil temp. In theory, a modern, short hopped light truck diesel could run into the same issues... if that's an truly an issue. So while the differences in ZDDP chemistry between a gas and dual rated diesel oil may exist, it seems doubtful it's a significant issue. I see the lack of optimal viscosity choices as more an issue, but it you are willing to get intothe more expensive dual-rate oils, that may not be much of an issue. Especially if you consider that many "classic" or late generation flat tappet engines were spec'ed of 10W30 or 10W40 oils that are esily matched in the HDEO realm.

See this reference from Automotive Lubricants Reference Book. High detergency is always bad for wear protection, as it also strips away the antiwear, extreme-pressure, and friction-modifier, and oil films from metal parts while it cleans them. Regarding primary and secondary ZDDP, it has to do more with the combustion temperature, which is greatly higher in diesel engines, than the oil temperature. Secondary ZDDP is more potent than primary ZDDP as an antiwear additive. Gasoline-engine oils have more secondary ZDDP as wear is a bigger concern in gasoline engines and there is less concern of ZDDP decomposition.

However, when attempts were made to introduce detergent additives into gasoline
engines, or to use diesel lubricants containing detergents in gasoline engines, there
were many failures with heavy wear resulting particularly in the cam and tappets.
The initial reactions were that these detergents were either chemically attacking the
metal or that their apparently colloidal metal compounds were actually abrading the
surfaces. This is now known not to be the case, and the effect is due to the highly
surface active nature of the detergents. which causes them to compete strongly for
possession of the metal surfaces with boundary layer and antiwear additives or
natural lubricity compounds in the oil. Because most detergents do not have
significant antiwear capability, the surfaces become relatively unprotected, and wear
takes place where loadings are heavy. To overcome this, the concentration of ZDDP,
or other antiwear additives, must be increased substantially for it to compete successfully
with the detergent and obtain some measure of occupation of the metal surfaces.

Today, ZDDP is the predominant antiwear additive used in crankcase oils, although
it is a class of additive rather than one particular chemical. The solubilizing groups
that enable the metal dithiophosphate to be soluble in oil can either be alkyl (straight
or branched chains) or aryl (aromatic rings). The antiwear activity (or rather the
sensitivity of the additive to commence giving antiwear protection) varies inversely
with the thermal stability of the particular structure. This increases with carbon number
and in the order secondary alkyl (the least stable and the most potent), through
primary alkyl to aryl types (the most stable but least potent). Diesel engines run
considerably hotter in the ring zone than gasoline engines, and ZDDP decomposition
tends to produce lacquer in this area. On the other hand, diesel engines, because of
their design and metallurgy, tend to have fewer wear problems than gasoline engines.
Thus, for a simple diesel oil, a more stable but less potent type of ZDDP can be
tolerated. However, when formulating multipurpose oils for use in gasoline engines,
high-speed passenger-car diesel engines, and larger diesel engines, it is necessary
to select carefully between the possible ZDDP types available and sometimes to
use balanced mixtures of two or more types. In some countries, restrictions on
lubricant phosphorus content, caused by concern for exhaust catalyst poisoning,
can limit the level of ZDDP that can be used. A phosphorus limit of 0.05% maximum
has been common for many years in Japan, and a limit of 0.1% maximum is
common elsewhere.


What this reference book is saying is really interesting:

The reason why diesel-engine oils have more ZDDP is not because they are meant to provide more protection against wear. On the contrary, it's only to make up for higher concentrations of detergents and dispersants in diesel-engine oils, which increase wear!

The long story short, you don't get more wear protection for your flat tappets with 1200 ppm of ZDDP in a diesel-engine oil than you get with 800 ppm ZDDP in a gasoline-engine oil, as the higher concentration in a diesel-engine oil is only to make up for wear-inducing detergents and dispersants. In addition, there are other things in a diesel-engine oil additive package that are not optimized for gasoline engines, including the type of ZDDP, amount of friction modifiers, type of viscosity-index improvers, etc. There is a reason why the additive companies make separate additive packages for CJ-4 and SN/GF-5 oils.
 
I've read that book too. I'll quote back part of your quote:

"However, when formulating multipurpose oils for use in gasoline engines,
high-speed passenger-car diesel engines, and larger diesel engines, it is necessary
to select carefully between the possible ZDDP types available and sometimes to
use balanced mixtures of two or more types."

I think that describes a modern HDEO, a balanced product.

You have still not commented on vintage oil ZDDP levels.
 
Originally Posted By: Jim Allen
I've read that book too. I'll quote back part of your quote:

"However, when formulating multipurpose oils for use in gasoline engines,
high-speed passenger-car diesel engines, and larger diesel engines, it is necessary
to select carefully between the possible ZDDP types available and sometimes to
use balanced mixtures of two or more types."

I think that describes a modern HDEO, a balanced product.

You have still not commented on vintage oil ZDDP levels.

Jim, Automotive Lubricants Reference Book was written by SAE, and I couldn't imagine any other explanation that would illuminate better on this subject than the excerpt from the book I posted above. It put the final period on this matter and everything is crystal-clear now.

Yes, they of course use a mix of primary and secondary ZDDP, and we knew that already. However, there is a good possibility that a diesel oil has more primary ZDDP than a gasoline oil, which has more secondary ZDDP. I won't reexplain the difference between the two and why diesel and gasoline oils tend to use different ratios of primary to secondary, as it's explained in the excerpt from the book I posted above.

The answer to your quiestion about vintage oil is explained in glory detail in the first paragraph in the excerpt. That's why I didn't reexplain it. But let me say it briefly -- if you don't have detergents, you need much smaller amounts of ZDDP.

So, why I have to keep reexplaining this -- I don't know -- as the excerpt clearly explained it and put the final word on it. But I will state the conclusion from the excerpt one more time, which is crucial: It's a big fad/myth/misconception that diesel oils (HDEOs) offer better wear protection, such as for flat-tappet engines, because they have more ZDDP (0 - 1200 ppm P) than gasoline-engine oils (600 - 800 ppm P). The only reason why HDEOs have more ZDDP is to make up for the high level of detergents, which increase wear. You will get no increased wear in a flat-tappet or other engine with an SN/GF-5-only gasoline-engine oil (PCMO) than you will with an HDEO. In fact, chances are that, in a gasoline engine, with an SN/GF-5-only PCMO, you will get less wear than with an HDEO, as the type of ZDDP used is more potent as an antiwear additive (as gasoline engines are more prone to wear than diesel engines) and the detergent levels are smaller, along with many other optimizations of additives for gasoline-engine use. Once again, this is clearly explained in the excerpt from the SAE book above and I will not explain it one more time.

That excerpt from the SAE book should be made a sticky thread in the HDEO section for those who are sucked into using HDEOs because they rather mistakenly assume the higher level of ZDDP will help them decrease wear in their gasoline-engine application, while they don't realize that HDEOs are more likely to cause increased wear in gasoline engines due to their high detergent levels and other reasons (less secondary ZDDP, additives not optimized for gasoline-engine use, etc.) explained above.
 
Originally Posted By: Gokhan
Regarding the "certification" of dual-certified (CJ-4/SM) oils, even API states that these oils may not be optimal for gasoline engines, as they don't meet every requirement of an SM-only or SN-only oil.

First off, unfortunately, the quotes you posted from the Cam-Shield people are filled with tripe. Their survival depends on us buying into the idea that there was much more ZDDP in oils of yesteryear and that an additive is the solution. Neither holds a lot of water.

Additionally, back in the day, just about every engine oil out there was dual rated. Was that a problem? Also, many of these older, high performance applications really don't have a need for the finest, most carefully tuned lubes available today. Modern engines aren't that sensitive. Older ones are even less so.

We're also exaggerating the detergency of HDEOs. Too many of these references are dated; Richard indicated how things have changed even within the lifespan of CJ-4. ULSD is the norm. TBN in HDEOs is lower than it used to be. We also shouldn't ignore cost. Some of us get HDEOs, even synthetic ones, at a significant discount. My price on Delvac 1 rivals that of conventional. That makes it a pretty easy choice.

Also, with reference to some of the ultra-low phosphorous HDEOs - those are usually easy to spot. Delvac 1 LE 5w-30 is advertised as such, yet is still dual rated; I'd probably run it without concern, either. Others with low/no ZDDP lack the gasoline rating altogether; those I'd avoid considering their not suitable for gasoline engines.
 
Originally Posted By: Garak
Originally Posted By: Gokhan
Regarding the "certification" of dual-certified (CJ-4/SM) oils, even API states that these oils may not be optimal for gasoline engines, as they don't meet every requirement of an SM-only or SN-only oil.

First off, unfortunately, the quotes you posted from the Cam-Shield people are filled with tripe. Their survival depends on us buying into the idea that there was much more ZDDP in oils of yesteryear and that an additive is the solution. Neither holds a lot of water.

Additionally, back in the day, just about every engine oil out there was dual rated. Was that a problem? Also, many of these older, high performance applications really don't have a need for the finest, most carefully tuned lubes available today. Modern engines aren't that sensitive. Older ones are even less so.

We're also exaggerating the detergency of HDEOs. Too many of these references are dated; Richard indicated how things have changed even within the lifespan of CJ-4. ULSD is the norm. TBN in HDEOs is lower than it used to be. We also shouldn't ignore cost. Some of us get HDEOs, even synthetic ones, at a significant discount. My price on Delvac 1 rivals that of conventional. That makes it a pretty easy choice.

Also, with reference to some of the ultra-low phosphorous HDEOs - those are usually easy to spot. Delvac 1 LE 5w-30 is advertised as such, yet is still dual rated; I'd probably run it without concern, either. Others with low/no ZDDP lack the gasoline rating altogether; those I'd avoid considering their not suitable for gasoline engines.

Perhaps you can shrug off the Cam-Shield reference but the SAE reference is quite clear and authoritative. You should read the SAE reference above carefully.

CJ-4 oils still have more dispersants than any other diesel oil of the past (CI-4 etc.), as they have excellent, never-before-seen soot control (which you don't need for your gasoline application). Dispersants also reduce the effectiveness of ZDDP as do detergents (see this reference).

If you think you need an xW-40 oil and you live in Canada, Mobil 1 0W-40 or similar, not Mobil Delvac HDEO, is the right oil for you. If you're OK with xW-30 viscosity, pick up any synthetic 0W-30 or synthetic 5W-30. I can't believe you would be picky on the price of the oil because you have a newer-model luxury car.
 
Originally Posted By: Gokhan

Perhaps you can shrug off the Cam-Shield reference but the SAE reference is quite clear and authoritative. You should read the SAE reference above carefully.



It is authoritative in defining general concepts but does it address this issue directly? I.e. what is the equivalency? Does 1200 PPM net ZDDP (primary and secondary) content in a dual rated HDEO, with all its extra dispersency and detergency additives, still exceed the level of anti-wear protection found in current SN levels? Or not? Can you answer that?

BTW, neither SN or CJ-4 existed when the book was written. And it does not appear to be an SAE book either. It was published in 2003 and given the timeframe of getting a manuscript from author to print, he was probably reflecting 2001 or 2002 technology. It's 2014 now and there have been many advances since, both in PCMO and HDEO.
 
I read what I could, since the link won't show me much beyond the cover. Nonetheless, from the quote you provided, nothing I read worries me in the least. Of course detergents and dispersants compete with AW compounds. That's nothing new or surprising, and has been observed in gasoline engine oils, too.

I certainly don't need a synthetic. Most of the time I have had the G, it's been on a steady diet of PYB 5w-30. But, I had some Delvac 1 ESP 5w-40 in stock and decided to use it up. Given the price and the much easier shopping experience, I'm considering sticking with it for the long run. Note that XOM specifically endorses it for high performance applications.

Do note something about M1 0w-40. If Delvac 1 ESP 5w-40 is inappropriate because it's dual rated, what makes M1 0w-40 appropriate? After all, it is an A3/B4 rated oil. A3 is for gas, B4 is for diesel. Hence, it's also a dual rated oil.
 
Originally Posted By: Jim Allen
Originally Posted By: Gokhan

Perhaps you can shrug off the Cam-Shield reference but the SAE reference is quite clear and authoritative. You should read the SAE reference above carefully.

It is authoritative in defining general concepts but does it address this issue directly? I.e. what is the equivalency? Does 1200 PPM net ZDDP (primary and secondary) content in a dual rated HDEO, with all its extra dispersency and detergency additives, still exceed the level of anti-wear protection found in current SN levels? Or not? Can you answer that?

BTW, neither SN or CJ-4 existed when the book was written. And it does not appear to be an SAE book either. It was published in 2003 and given the timeframe of getting a manuscript from author to print, he was probably reflecting 2001 or 2002 technology. It's 2014 now and there have been many advances since, both in PCMO and HDEO.

You're now being nothing but argumentative.

It's a SAE publication -- see the second page.

The knowledge ten years ago (when this book was published) applies more than well enough to the present day. On top of that, the book explained the history of ZDDP use in oil and answered your question regarding vintage oil -- yet, you're still being childishly argumentative. You simply don't understand how science works. You must think scientific publications are like iPhones that need to be updated every year. We are not discussing the itty-bitty difference in CJ-4 & CI-4 or SN and SM here. The general ideas in the book apply extremely well to this very particular subject of this thread.

The questions you're asking now are becoming argumentative and ridiculous. No one can answer exactly how much wear protection a particular oil or a given amount of ZDDP offers and we are not here to discuss that. We have been just discussing whether an HDEO or PCMO is generally more suitable for gasoline-engine use, especially one with flat tappets, and that has now been well-answered.
 
Originally Posted By: Garak
Do note something about M1 0w-40. If Delvac 1 ESP 5w-40 is inappropriate because it's dual rated, what makes M1 0w-40 appropriate? After all, it is an A3/B4 rated oil. A3 is for gas, B4 is for diesel. Hence, it's also a dual rated oil.

Hi Garak,

No, I wouldn't consider A3/B4 dual-rated, as all oils fit in one of the ACEA A/B categories. B categories can hardly be considered true diesel categories, as there is virtually no oil sold that doesn't fall into an "A/B" category. In other words, for example, any Pennzoil yellow bottle is a dual-rated oil in that sense. The categories in ACEA corresponding to the API CJ-4 etc. categories are ACEA E9 etc. -- the true heavy-duty-engine-oil categories.

See this reference for the understanding of the ACEA categories.
 
Originally Posted By: Gokhan

You're now being nothing but argumentative.


Since you want to get personal, I merely am mirroring your snotty, condescending, holier-than-thou style. You've read a book and now you're an instant expert claiming to understand it all and anyone who doesn't bow and scrape doesn't know squat. That's quite your style..

Originally Posted By: Gokhan

It's a SAE publication -- see the second page.


Ain't seeing it. Says it's a 2003 pub from Elsevier B.V. in the Netherlands. No SAE info. If it matters.

Originally Posted By: Gokhan


The knowledge ten years ago (when this book was published) applies more than well enough to the present day. On top of that, the book explained the history of ZDDP use in oil and answered your question regarding vintage oil -- yet, you're still being childishly argumentative. You simply don't understand how science works. You must think scientific publications are like iPhones that need to be updated every year. We are not discussing the itty-bitty difference in CJ-4 & CI-4 or SN and SM here. The general ideas in the book apply extremely well to this very particular subject of this thread.

No one can answer exactly how much wear protection a particular oil or a given amount of ZDDP offers and we are not here to discuss that. We have been just discussing whether an HDEO or PCMO is generally more suitable for gasoline-engine use, especially one with flat tappets, and that has now been well-answered.


Again the personal insults. Basically I agree that the concepts don't change too much but I disagree that the wear protection can't be measured. It can. Whether it has or not in the context of this discussion, we do not know. The practical answer to the question is that an HDEO is probably more than adequate for a flat tappet engine. Is it optimal? I never said that it was, just that it's a viable low cost, easy access option, a generally suitable option, with few downsides for the average joe.
 
How is it personal insults when I'm pointing out that you're being argumentative, especially when you're being so? How many references have you posted so far to counter my claims? I've answered many of your questions and your response every time has been to come up with a new question.

I told you to look at the second page (copyright page) of the book but you didn't. It was published by SAE in September 2004, 9 years 4 months ago. It's the second edition:

lubricants_reference_cover.jpg


lubricants_reference.jpg


You dismissed a nine-year-old authoritative SAE book on engine oil saying that it was outdated.

Sure, the wear can be measured. It's measured by the Sequence IVA (ASTM D6891) test. However, good luck finding any results of the test disclosed. The only results disclosed I am aware of were during the Mobil 1 - Valvoline SynPower - Castrol Edge war. The maximum acceptable wear limit is 90 microns and the SM version of Mobil 1 had showed 180 microns of wear, according to private tests:

artwor55.gif


How is HDEO more affordable than PCMO? The original question in this thread was whether a flat-tappet engine could benefit from higher levels of ZDDP in CJ-4 oils. The answer, according to the references I posted, one of them being authoritative, is probably not, the reason having got to do the with type of ZDDP (primary vs. secondary), amount of dispersants and detergents, and optimization of the additive packages for gasoline or diesel applications. Would a CJ-4 be adequate for flat tappets? Probably, yes, and I've never said no. However, being adequate wasn't the original question. The original question asked whether a CJ-4 oil was a better choice than an SN/GF-5 oil. The answer, according to this reference, is no, and everything it says makes perfect sense. In fact, chances are that an SN/GF-5 oil provides better wear protection for flat tappets than a CJ-4 oil. Extra ZDDP in CJ-4 oils is to make up for wear induced by extra dispersants and detergents in CJ-4 oils, not to provide additional wear protection surpassing wear protection in gasoline engines. In fact, gasoline engines are more wear-prone and they demand more wear protection than diesel engines.

You can keep being argumentative and claim that we still don't know for sure because we have never seen the Sequence IVA results. Yes, you can never be sure which oil provides less wear in Sequence IVA or in real-life driving. However, we can still give a general answer to the question asked here originally.

After being told about the different types of ZDDP (primary, secondary, or a certain mix of a certain ratio of the two) used in diesel vs. gasoline oil and wear-inducing dispersants and detergents in diesel oil, if someone still thinks that 1000 ppm P of ZDDP in a CJ-4 oil will offer more wear protection for his flat tappets than 800 ppm P of ZDDP in an SN/GF-5 oil, well...

Anyway, Jim, I have no hard feelings here -- I was just frustrated by your seemingly argumentative responses.
smile.gif
 
Originally Posted By: Gokhan
See this reference for the understanding of the ACEA categories.

I am familiar with the ACEA sequences. I would suggest you do have to look at the B as true diesel categories, and not all oils meet ACEA specifications. PYB certainly does not. Pennzoil certainly has a different bar to meet when it's dealing with PYB versus PU in A5/B5 or A3/B4 types. Heck, we even have people using ACEA E rated oils in various VW diesels that call for VW spec oils.

With respect to my Infiniti, "luxury car" or not, its oil specifications are very modest. It calls for SM/GF-4 in North America, with a bit wider range elsewhere. Generally speaking, the engine isn't calling for anything too terribly specific, like a certain phosphorous or SAPS content.

I'd be interested to hear from Doug or Shannow about the 15w-40 grades commonly used down under. I assume the 15w-40 commonly used in gassers there is dual rated like most 15w-40 grades here.
 
Another issue, aside from ZDDP, is viscosity. Some of these engines were contemporary with a 10w-30 with a higher HTHS than what one sees in an ILSAC rated oil. Aside from ZDDP, some people do choose an HDEO over a PCMO for certain applications due to the higher HTHS, without having to jump to a 10w-40, 20w-50, or a synthetic in the process.

Personally, I never had issues with ILSAC rated oils in older stuff unless there were serious fuel dilution issues.
 
Originally Posted By: Garak
Originally Posted By: Gokhan
See this reference for the understanding of the ACEA categories.

I am familiar with the ACEA sequences. I would suggest you do have to look at the B as true diesel categories, and not all oils meet ACEA specifications. PYB certainly does not. Pennzoil certainly has a different bar to meet when it's dealing with PYB versus PU in A5/B5 or A3/B4 types. Heck, we even have people using ACEA E rated oils in various VW diesels that call for VW spec oils.

With respect to my Infiniti, "luxury car" or not, its oil specifications are very modest. It calls for SM/GF-4 in North America, with a bit wider range elsewhere. Generally speaking, the engine isn't calling for anything too terribly specific, like a certain phosphorous or SAPS content.

I'd be interested to hear from Doug or Shannow about the 15w-40 grades commonly used down under. I assume the 15w-40 commonly used in gassers there is dual rated like most 15w-40 grades here.

I was primarily pointing out that the equivalent of API CJ-4 is ACEA E9, not ACEA Bx.

I don't think ACEA licenses A and B categories separately any more -- they all seem to come as A/B combined at the present. ACEA Bx is possibly more similar to the old API CF. It's certainly not meant for heavy-duty engines as the API Cx-4 or ACEA Ex categories.
 
Originally Posted By: Garak
Another issue, aside from ZDDP, is viscosity. Some of these engines were contemporary with a 10w-30 with a higher HTHS than what one sees in an ILSAC rated oil. Aside from ZDDP, some people do choose an HDEO over a PCMO for certain applications due to the higher HTHS, without having to jump to a 10w-40, 20w-50, or a synthetic in the process.

Personally, I never had issues with ILSAC rated oils in older stuff unless there were serious fuel dilution issues.

xW-30 oils with higher HTHS values are nothing but xW-35 oils. Both the KV @ 100 and HTHSV are about 15% higher than a typical xW-30, with the same proportional increase -- so, an xW-35 so to speak.

I wouldn't be that picky about viscosity and if the manufacturer recommended such an oil ("xW-35" so to speak), I would pick xW-40 in the case of a diesel engine or flat-tappet engine (because of wear concerns) and either the xW-30 or xW-40 for a modern gasoline engine depending on driving style and particular engine. For gasoline engines, if wear is not a concern, I like smaller viscosity because of lower (= better) oil pressure, better fuel economy, and more compliance with the various GF-5 specs.
 
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