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#3238941 - 01/06/14 01:04 AM Re: CJ-4 oil for older flat tappet engines.. [Re: Gokhan]
Garak Offline


Registered: 12/05/09
Posts: 9879
Loc: Regina, Saskatchewan, Canada
Originally Posted By: Gokhan
Also note that Non-ILSAC (non-GF-5) SN oils are exempt from the 800 ppm P ZDDP maximum limit. This means xW-40 and xW-50 SN oils have no ZDDP maximum limit. Also, high-mileage SN oils of any viscosity have no ZDDP maximum limit, as they are not GF-5. ZDDP maximum limit is imposed by the "Resource Conserving" (of the GF-5) designation, not the SN designation by itself.

The problem is, though, that just because certain viscosity or certification examples have no limitation doesn't mean they pour the stuff in. Plenty of non-ILSAC rated oils, HM examples, or pre-limitation examples had rather low zinc and phosphorous concentrations, lower, in fact, than some modern ILSAC formulations.

That's why I do like things such as most HDEOs or VR1 for such applications. At least we have confirmed, elevated additive levels.

Did I ever mention that a local WM here sells VR1 cheaper than normal PCMO? wink
_________________________
Plain, simple Garak.

2008 Infiniti G37 coupe - Mobil Delvac 1 ESP 5w-40, Hastings LF113
1984 F-150 4.9L six - Quaker State GB 10w-30, Wix 51515

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#3239037 - 01/06/14 07:03 AM Re: CJ-4 oil for older flat tappet engines.. [Re: Ponch]
Jim Allen Offline


Registered: 08/12/05
Posts: 4477
Loc: NW Ohio
Most of the current crop of HDEOs have MORE ZDDP than the PCMO oils from back in the day. If you go to Blackstone Lab's website and find the newsletters from 2012, you will see a batch of vintage oil VOAs. They tested unused oils as old as the 1930s and 1940s. If you look at the more recent oils from the '60s and '70s, you will find some with very little ZDDP and some with very moderate amounts under 1000 ppm. A few showed on 100-300 ppm. A few are as high as 1200 ppm. I have posted some VOAs from the late '80s and they were around 1000 ppm. In many cases even the current PCMO has enough zinc for low performance flat-tappet applications that aren't breaking in a new cam. I think one is prudent to want a bit more ZDDP than 800 ppm and HDEOs are but one alternative. You might look at the QS Defy line as well. The HDEOs are a good choice but the viscosity choices are more limited.
_________________________
Jim Allen
Keepin' the Good Old Days of Four Wheeling Alive

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#3239362 - 01/06/14 12:06 PM Re: CJ-4 oil for older flat tappet engines.. [Re: Ponch]
Gokhan Online   content


Registered: 12/29/10
Posts: 1322
Loc: Los Angeles, California
I would go with Mobil 1 0W-40 SN -- 1000 ppm P. Get a 5 qt jug from Walmart.

Here is the table of Mobil 1 oils (PDF file), showing their ZDDP levels. Some go up to 1750 ppm P, well above the CJ-4 maximum limit. GF-5 minimum and maximum limits are 600 - 800 ppm P. CJ-4 minimum and maximum limits are 0 - 1200 ppm P (no minimum limit). Also note that the type of ZDDP used in diesel-engine oil is more an antioxidant than an antiwear additive. This is in contrast to gasoline-engine oils, where the type of ZDDP used is more an antiwear than an antioxidant additive.

Here is the Q&A from the Mobil 1 Web site:

Question:
Mixing Motor Oil to Reach the Right ZDDP Level for Classic Cars
For an older, flat tappet, performance motor with inherent cam wear issues is there any benefit to mixing high ZDDP Mobil 1 Racing 4T 10W-40 to Mobil 1 High Mileage 0W-30 oil? The 15W-50 creates TOO MUCH oil pressure. It would be nice if you had a product for 'Classic' cars, high ZDDP, 0W-30 and 0W-40. I have used nothing but Mobil 1 for 15+ years.
-- Bill McCauley, Tallmadge, OH

Answer:
Mobil 1 0W-40 already contains a higher level of ZDDP (1000 ppm) that could benefit your flat tappet engine. We also have a Mobil 1 High Mileage 10W-40 (1000 ppm); see our table listing the phosphorous levels for all Mobil 1 synthetic motor oils.
_________________________
1985 Toyota Corolla LE, 4A-LC engine, ~ 255,000 M
Toyota (by ExxonMobil) SN/GF-5 0W-20 Synthetic
Toyota 90915-YZZF2 filter, 90430-12031 drain gasket

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#3239392 - 01/06/14 12:22 PM Re: CJ-4 oil for older flat tappet engines.. [Re: Gokhan]
Gokhan Online   content


Registered: 12/29/10
Posts: 1322
Loc: Los Angeles, California
Originally Posted By: Gokhan
Also note that the type of ZDDP used in diesel-engine oil is more an antioxidant than an antiwear additive. This is in contrast to gasoline-engine oils, where the type of ZDDP used is more an antiwear than an antioxidant additive.

The following is a good read on why you shouldn't use diesel-engine oils in flat-tappet gasoline engines:

Why NOT diesel or racing oil? (link from Cam-Shield oil treatment)

Contrary to the current internet buzz that diesel oil is the oil to use in a gasoline flat tappet cam engine, the correct oil to use on a continuous basis in your classic car's flat tappet cam engine is an oil designed for gasoline engines that contains the correct level of ZDDP anti-wear protection. Similarly, a race oil is not recommended for continued use in a street driven gasoline engine.

If you look on the back of a bottle of oil you will see the API performance classification for the oil. Diesel oils with API credentials of CI-4, CI-4 Plus, CJ-4 will typically have Zinc levels around 1100 parts per million (ppm). 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. For muscle cars and hot rods with higher valve spring pressures, 1600 ppm will give uncompromised protection. Race cars generally need around 2000 ppm. Break-in of a new cam is generally best protected with around 2500 ppm (in addition to the molybdenum cam lobe lube). Current API SM/ILSAC GF-4 gasoline engine oils have incredible performance capabilities and will have approximately 850 ppm of Zinc, but will need to be supplemented with ZDDP to make them suitable for use in flat tappet cam engines in classic cars, hot rods and race cars. It is extremely important to add a highly concentrated ZDDP product so as not to dilute the oil and thus impact the performance integrity of the engine oil.

Here are the differences between diesel engine oil and gasoline engine oil. In a modern diesel engine there is substantial exhaust soot contamination that the engine oil must contend with. Diesel oil is designed with much higher levels of detergency and dispersency to fight the soot contamination. Like ZDDP anti-wear chemistry, detergents are a surface active chemistry and compete directly for space on metal surfaces, such as the cam lobe and lifter face. So, in practice, the effective level of Zinc anti-wear is a bit lower than what we expect it to be based solely on chemical analysis. Additionally, the ZDDP that is generally used in diesel formulas is primary ZDDP (which activates at higher engine temperatures) since a diesel engine runs predominantly at operating temperature. In a gasoline engine, we must have both primary and secondary ZDDP (which activates at lower temperatures) since the engine will experience a significant number of cold starts. Also, the viscosity modifier polymers that are used in multi-viscosity engine oil to prevent viscosity loss at operating temperature (to protect the bearings) are different for diesel oil and gasoline oil. Diesels operate at essentially the same rpm all day long and need polymers that are shear stable to protect the bearings. Gasoline engines experience many large ranges of rpm during operation and require polymers that have both shear stability and thickening efficiency capability to protect the bearings.

Race oil formulas are typically designed with reduced levels of detergency and dispersency to improve performance of the anti-wear and friction modifier chemistries. Race oil is typically changed very frequently and race engines are typically re-built frequently. For a street driven gasoline engine, the correct levels of detergency and dispersency are required to prevent deposit formation (particularly at the piston rings), and sludge formation, from contaminants. This becomes more important to classic car owners who may only drive the vehicle occasionally and who change the oil once or twice a year.
_________________________
1985 Toyota Corolla LE, 4A-LC engine, ~ 255,000 M
Toyota (by ExxonMobil) SN/GF-5 0W-20 Synthetic
Toyota 90915-YZZF2 filter, 90430-12031 drain gasket

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#3239457 - 01/06/14 01:31 PM Re: CJ-4 oil for older flat tappet engines.. [Re: Gokhan]
Jim Allen Offline


Registered: 08/12/05
Posts: 4477
Loc: NW Ohio
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?
_________________________
Jim Allen
Keepin' the Good Old Days of Four Wheeling Alive

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#3239483 - 01/06/14 01:50 PM Re: CJ-4 oil for older flat tappet engines.. [Re: Ponch]
Jim Allen Offline


Registered: 08/12/05
Posts: 4477
Loc: NW Ohio
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.
_________________________
Jim Allen
Keepin' the Good Old Days of Four Wheeling Alive

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#3239578 - 01/06/14 03:18 PM Re: CJ-4 oil for older flat tappet engines.. [Re: Jim Allen]
Gokhan Online   content


Registered: 12/29/10
Posts: 1322
Loc: Los Angeles, California
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.
_________________________
1985 Toyota Corolla LE, 4A-LC engine, ~ 255,000 M
Toyota (by ExxonMobil) SN/GF-5 0W-20 Synthetic
Toyota 90915-YZZF2 filter, 90430-12031 drain gasket

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#3239623 - 01/06/14 03:56 PM Re: CJ-4 oil for older flat tappet engines.. [Re: Gokhan]
Doug Hillary Offline


Registered: 05/30/03
Posts: 4788
Loc: Airlie Beach Australia
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!
_________________________
Regards
Doug

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#3239660 - 01/06/14 04:45 PM Re: CJ-4 oil for older flat tappet engines.. [Re: Doug Hillary]
Gokhan Online   content


Registered: 12/29/10
Posts: 1322
Loc: Los Angeles, California
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.
_________________________
1985 Toyota Corolla LE, 4A-LC engine, ~ 255,000 M
Toyota (by ExxonMobil) SN/GF-5 0W-20 Synthetic
Toyota 90915-YZZF2 filter, 90430-12031 drain gasket

Top
#3239690 - 01/06/14 05:16 PM Re: CJ-4 oil for older flat tappet engines.. [Re: Gokhan]
Jim Allen Offline


Registered: 08/12/05
Posts: 4477
Loc: NW Ohio

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.
_________________________
Jim Allen
Keepin' the Good Old Days of Four Wheeling Alive

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#3239713 - 01/06/14 05:32 PM Re: CJ-4 oil for older flat tappet engines.. [Re: Jim Allen]
Gokhan Online   content


Registered: 12/29/10
Posts: 1322
Loc: Los Angeles, California
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.
_________________________
1985 Toyota Corolla LE, 4A-LC engine, ~ 255,000 M
Toyota (by ExxonMobil) SN/GF-5 0W-20 Synthetic
Toyota 90915-YZZF2 filter, 90430-12031 drain gasket

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#3240236 - 01/07/14 05:36 AM Re: CJ-4 oil for older flat tappet engines.. [Re: Ponch]
Jim Allen Offline


Registered: 08/12/05
Posts: 4477
Loc: NW Ohio
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 Allen
Keepin' the Good Old Days of Four Wheeling Alive

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#3240480 - 01/07/14 10:24 AM Re: CJ-4 oil for older flat tappet engines.. [Re: Jim Allen]
Gokhan Online   content


Registered: 12/29/10
Posts: 1322
Loc: Los Angeles, California
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.
_________________________
1985 Toyota Corolla LE, 4A-LC engine, ~ 255,000 M
Toyota (by ExxonMobil) SN/GF-5 0W-20 Synthetic
Toyota 90915-YZZF2 filter, 90430-12031 drain gasket

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#3240525 - 01/07/14 11:09 AM Re: CJ-4 oil for older flat tappet engines.. [Re: Gokhan]
Garak Offline


Registered: 12/05/09
Posts: 9879
Loc: Regina, Saskatchewan, Canada
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.
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Plain, simple Garak.

2008 Infiniti G37 coupe - Mobil Delvac 1 ESP 5w-40, Hastings LF113
1984 F-150 4.9L six - Quaker State GB 10w-30, Wix 51515

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#3240551 - 01/07/14 11:32 AM Re: CJ-4 oil for older flat tappet engines.. [Re: Garak]
Gokhan Online   content


Registered: 12/29/10
Posts: 1322
Loc: Los Angeles, California
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.
_________________________
1985 Toyota Corolla LE, 4A-LC engine, ~ 255,000 M
Toyota (by ExxonMobil) SN/GF-5 0W-20 Synthetic
Toyota 90915-YZZF2 filter, 90430-12031 drain gasket

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