ZDDPlus™ - ZDDP Additive for Classic Cars - Agricultural Equipment & More

ZDDPlus™ Sponsoring F.A.S.T Race Series !!

After 70+ years of trouble-free, metal-metal engine protection, the E.P.A. is forcing ZDDP (Zinc Dialkyl Dithio Phosphate = Zinc and Phosphorus) from domestic motor oil. If your engine was designed prior to the 1990s, your non-roller lifters require ZDDP in your motor oil to avoid premature deterioration. Don’t let your lifters run metal-to-metal. Keep ZDDP, via ZDDPlus™, in your motor oil. Add 4 oz of ZDDPlus™ at every 4 to 5 quart oil change. One bottle of ZDDPlus™ contains more ZDDP than two bottles of GM’s EOS, which is designed for break-in use ONLY

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Tech Briefs & Guides:

TechBrief 1 - Introducing ZDDPlus™
TechBrief 2 - ZDDP and Cam Wear - Just Another Engine Oil Myth
TechBrief 3 - ZDDP and Engine Break-in (being revised, available soon)
TechBrief 4 - Oil & Additive Testing
TechBrief 5 - Racing Oil as a Replacement for SM Oil
TechBrief 6 - Diesel Oil Use in Classic and High-Performance Gasoline Engines
TechBrief 7 - Oil Additive Dosing and Dilution
TechBrief 8 - Automotive & Oil Industry vs. the Aftermarket Viewpoint on ZDDP
TechBrief 9 - ZDDP and Oil Filters

ZDDPlus™ - Material Safety Data Sheet

*Certified Test Results*
	*Checkout the* ZDDP Certified Lab Test Results Place a 4 ounce bottle of ZDDPlus™ into a typical 5 quart (160 ounce) oil tank. Use ZDDP with confidence!

ZDDPlus™ is a product offered by car enthusiasts
to meet the needs of classic car aficionados.

The automotive industry in general is changing in response to the environmental and financial pressures of today, with little concern for the classic car industry. We are engineers and automotive technicians by trade, and bring many years of problem solving experience to the task of keeping our classic cars operational and running better than new. We hope that one of the solutions we have designed for our own use will meet your needs as well. We have developed ZDDPlus™ to address the needs of classic car owners for an oil that will meet the specifications of the original oil for which their engines were designed.

Why do we need ZDDPlus™ ?

     As part of an effort to reduce vehicle emissions, the U.S. EPA offers vehicle manufacturers "credits" for early implementation as well as penalties for violation of emission reduction standards. The EPA's program called for 100,000-mile catalytic converter life by 2004, 120,000 miles by 2007, and 150,000 miles by 2009. To achieve these goals, automotive manufacturers have pressured their oil suppliers to remove substances from motor oils that would shorten the service life, including the proven EP (extreme pressure) additive ZDDP (zinc dialkyldithiophosphate). Zinc and phosphorus from the ZDDP can be present in small amounts in the exhaust gas of an engine depending on the amount of oil which is consumed in combustion. These elements can coat the catalyst reducing the amount of catalyst exposed to the exhaust gases, ultimately increasing emissions at the tailpipe. As a result of the EPA mandate, the ZDDP level in engine oils has been declining since the mid-1990s, roughly coinciding with the implementation of OBDII.

     ZDDP has been an important additive to engine oils for over 70 years, and has an excellent track record at protecting the sliding metal-to-metal cam lifter interface. Historically, ZDDP has been added to oils in amounts resulting in approximately 0.15% phosphorus, and 0.18% zinc. ZDDP protects by creating a film on cams and flat lifter contact points in response to the extreme pressure and heat at the contact point. The film of zinc and phosphorus compounds provides a sacrificial wear surface protecting the base metal of the cam and lifter from wear. In the course of normal service, this conversion of ZDDP to zinc and phosphorus compounds depletes the ZDDP level in the oil. Studies show that depending on the specific engine and severity of duty, after 2000-4000 miles of operation, the level of ZDDP can drop below that considered adequate to provide wear protection to the cam and lifters.

     According to the SAE Tech Bulletin # 770087 [1] , operation of a flat tappet engine without adequate EP additives such as ZDDP quickly leads to lifter foot scuffing and cam lobe wear. Camshafts are typically only surface hardened leaving the core ductile for strength. According to the SAE Bulletin, once cam lobe wear reaches 0.0002, "subsequent wear is usually rapid and catastrophic." Two ten-thousandths of an inch is one fifth the thickness of an average human hair.

     In order to make engines last in the absence of ZDDP, virtually all IC (internal combustion) engines designed in the last ten years utilize roller lifters. Today, ZDDP has been removed from practically all automotive engine oils, rendering them unsuitable for use with older engines with non-roller lifters.

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Why is it being removed?

Because contemporary engines with roller bearings no longer require the additional protection of Zinc and Phosphorus. Not true for classic cars, tractors, muscle cars, etc. Also removing the Zinc and Phosphorus from motor oil increases the life of the catalytic converter. But classic cars, tractors, etc., don’t have cats! Also, as part of its ongoing effort to reduce vehicle emissions, the EPA has mandated that emission systems must have a service life exceeding 120,000 miles. To achieve this, automotive manufacturers have required oil suppliers to remove additive packages from motor oils that could reduce emissions compliance.

ZDDPlus™ is the ONLY EP (Extreme Pressure) component which re-establishes the ZDDP levels that our classic car engines were designed for, while allowing the car owner to use the base oil of their choice. While some off-the-shelf additives may have some ZDDP, the amount per bottle is small, and when enough is used to get the proper concentration of ZDDP, there is a quart or more of unspecified oil that comes along with it. This dilution of 20% of your oil with an unspecified oil also means that there is 20% less of the proper additive package. The chart below compares the amount of ZDDP in ZDDPlus™ to GM EOS, an additive which claims to provide ZDDP based wear protection.

[1] Pless, Loren G., and Rodgers, John J., ‘Cam and Lifter Wear as Affected by Engine Oil ZDP Concentration and Type’, SAE pub 770087, 4 (1977)

F Read the Tech Brief for more information

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What's In Our Oil ?

As lubrication technology improves, so does the base oil used in the manufacture of engine oils. Oils are also changed and updated in response to advancements in engine technology.

Modern engine oil is a precise mix of a base oil with additives totaling almost 10% of the oil by volume. Pound for pound these additives are each more expensive than the base oil, and oil companies are in business to make a profit. Common sense says that these additives are there with Modern engine oil is a multi-purpose fluid in an engine, carrying the heat away from hot spots and releasing it in the sump as well as providing lubrication to critical areas which need protection against wear. Different additives are put in the oil in order to address the needs of each specific engine system that is supplied with oil:

The crankshaft and connecting rod bearings discharge oil into the spinning reciprocating assembly, and an anti-foaming additive keeps the oil from turning into foam.

The heat developed on high-pressure contact areas can exceed the breakdown temperature rating of the base stock, so heat stabilizers are added in order to fight viscosity breakdown and ashing.

In a multi-viscosity oil, the multi-viscosity characteristic is established by an additive.

Acids and byproducts of combustion are neutralized by another additive.

A dispersant additive helps keep combustion particulates from clumping.

Detergents are added to lower the surface tension to a specific value to help keep contaminants in suspension and off of the metal engine parts. Some detergents also interact with the EP additive to gain an additional level of wear protection.

The sliding cam-to-cam-follower interface in a non-roller lifter engine requires a special EP additive, which has historically been the ZDDP that is now reduced in all API rated automotive oils.

ZDDPlus™ contains the proper amount of ZDDP to give at least 0.18% zinc and 0.13% phosphorus level when a single 4 oz. bottle is added to a normal 5-quart oil change. This level of zinc and phosphorus is the level designed into pre-OBDII oils. Using ZDDPlus™ affords you total control over the characteristics of the oil in the engine by allowing you to use the full 5 quarts of a high-grade automotive oil of your choice.
F Read the Tech Brief (Page 3) for more information

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What about off-the-shelf additives and supplements?

API oils have always been more than adequate for the engines designed when the oil was current. The use of current API grade oils has always been adequate to satisfy car manufacturer's requirements and warranty demands. Historically, with few exceptions, newer API grades have superseded the performance of their predecessors. The removal of ZDDP has resulted in a clear change to that philosophy. It has never been necessary or desirable to include additives or supplements to any API rated oil to meet car manufacturer's specifications or warranty requirements. In virtually all cases, off-the-shelf additives amount to little more than automotive snake oil. Current additive technology has yet to develop an EP anti-wear agent as effective as ZDDP. Consequently, if these additives actually had adequate levels of ZDDP, they would be incompatible with modern engines and void manufacturer's warranties.
Due to this unprecedented turn of events in emissions requirements, ZDDPlus™ should not be confused with an off-the-shelf additives. ZDDPlus™ should be considered a replacement for a missing oil component critical for older cars.

Current additive technology has yet to develop an EP anti-wear agent as effective as ZDDP.

Why Add ZDDPlus™ ?

ZDDPlus™ is not a typical oil additive. By adding a small 4 ounce bottle of ZDDPlus™ at every oil change, an adequate amount of Zinc and Phosphorus will continue to protect your classic engine.
ZDDPlus™ simply maintains the Zinc and Phosphorus
that has recently been removed.

Why Can't We Use Diesel CI/CJ-4 Rated Oils?

     There are some diesel engine rated oils on the market which may still have some ZDDP in them. There are problems associated with using these oils in a normal gasoline engine which can become severe in a high-performance gasoline engine. One issue is the high amount of detergent additive, and another is the high viscosity.

     High detergent oil has a lower surface tension and lower shear pressure rating which can cause higher bearing wear in gas engines. A diesel engine needs oil with very high detergent capabilities in order to hold the large amount of combustion byproducts in suspension, but it is not optimized for a gasoline engine. The bearing journal size-to-displacement ratio on a gasoline engine is designed around the use of a lower detergent oil and relies on a high-shear rating to the oil.

     The other problem with high detergent oil is that it actually reduces the friction reduction that the ZDDP affords, especially in a high-performance, high valve spring pressure engine.

     The viscosity rating of most diesel rated oils is higher than optimum for our higher revving gasoline engines, and can cause oil starvation in bearings at high rpms.
F Read the Tech Brief for more information

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Why Can't We Use Racing Oils?

There are some racing oils which maintain a level of ZDDP. Racing oils are optimized for short term severe duty, in contrast to an oil that has been designed for day in, day out street operation. The additive package in a racing oil does not have the same detergent characteristics which are designed into extended service oils. As a result, racing oils may not have the capability of neutralizing acids and keeping contaminants in suspension. Also, the breadth of choice of viscosity, so important to correct street engine operation over a broad temperature range, is not available in racing oils.

By using ZDDPlus™ in addition to a modern high-quality oil of the proper viscosity for your gasoline engine, the correct EP lubrication level is established, and the oil characteristics remain optimized for your engine.r engine.

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FAQ - Frequently Asked Questions

What is ZDDPlus™ ?

     ZDDPlus™ is an oil supplement that contains very high concentrations of the well-known additive ZDDP (Zinc Dialkyl Dithiophosphate), which has been the primary EP (extreme pressure) ingredient in all quality motor oils for over 70 years. However, beginning in the late 1980s, the concentration has been greatly reduced as newer oil classifications have come on the market.
F Read the Tech Brief for more information

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Why do I need ZDDP?

     The EPA has put stricter emission requirements on new cars that influenced manufacturers to remove ZDDP from motor oils. If you have an older car that was specified to use SF (1988) or earlier motor oil, its design requires ZDDP. Your older performance car could be damaged with the use of modern SM oils prevalent today. Cars equipped with flat tappet cams need ZDDP because of the high-pressure points. Newer cars have roller rockers and ZDDP is not needed in those applications

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What do the oil grades such as "SF" indicate ?

In the API (American Petroleum Institute) classification system, "S" and "C" are the two basic application categories of oil. "S" is intended for gasoline use and "C" is intended for diesel use.

"A" was the first grade in each category and resulted in "SA" and "CA" grade oils. Each designation progressed farther up the alphabet as new grades of oil were introduced. The newest grades are "SM" and "CJ" respectively. "SF" was for 1988 and older engines.

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Aren't the newer oils better than the older oils?

     Historically, every new grade of oil introduced since the 1930's was better than the previous grade and could be considered "improved" with one exception. The original SA grade was straight mineral oil (non-detergent non-additives) and SB contained additives which could not be used in the earliest cars specified for SA. While it is true that SM oils are better for NEW cars, they are NOT better for the OLDER cars equipped with flat tappet camshafts. Simply put, the newer, better oils are not backward compatible for older cars primarily due to the gradual reduction of ZDDP starting with SG grade introduced in 1988. In the next few years, it will be eliminated completely from oil.

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How much ZDDPlus™ should I add to my oil?

     One bottle of ZDDPlus™ will raise the ZDDP concentration level of SL or SM oil to the standards that were in place when SF (or earlier) oil was specified. (SL and SM is the current category available today).

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What if my oil already has some ZDDP?

    ZDDP is most effective if the concentration is between 0.18 and 0.2 % by weight. Tests have shown that concentrations above this amount, up to as much as several percent, have no effect except to prolong additive life. The current oils available today contain very little ZDDP.

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Can I use ZDDPlus™ with regular or synthetic oils?

     Yes, ZDDPlus™ should be compatible with all conventional and synthetic oils intended for automotive use. Virtually all of these current oils have had some amounts of ZDDP for years, and it continues to be decreased in available oils.

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What is the shelf life of ZDDPlus™ ?

     The shelf life of ZDDPlus™ is essentially the same as regular motor oil (many years), as long as a few conditions are met. The temperature should be kept below 120 degrees F and above 0 degrees. You need to keep it sealed until it is mixed with motor oil. ZDDPlus™ has a tendency to absorb moisture, not unlike brake fluid. Absorption of water will degrade its performance, although heating it above 100C until it is not cloudy will restore it.

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When should ZDDPlus™ be added?

     Anytime, but the best time is when you get the oil changed. A single 4-oz bottle is the correct concentration for a 4- to 5-quart oil change. This will bring the oil back to SF specifications.

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How long does ZDDPlus™ last?

     ZDDPlus™ is a sacrificial additive, meaning that in the process of working, it is depleted. ZDDPlus™ should last the life of a normal oil change as specified by the manufacturer of the car, but attention should be given to the categories of service known as "normal" and "severe" conditions. Severe includes stop-and-go driving and short trips, which result in shortened service life of not only ZDDPlus™ , but most of the other additives in the oil.

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Why haven't I heard more about this problem?

      The general public, as a rule, has nothing to be concerned about. The people that need to be concerned are owners of older classic cars and performance cars. After the SF category, the amount of ZDDP has gradually been reduced as each new API category is introduced. Had ZDDP been removed completely after 1988 (SF), the scramble for an alternative would have been a big concern. But, since it happened gradually, the concerns were not so obvious.

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Why should ZDDPlus™ not be used in OBD cars?

      The key ingredient of ZDDPlus™ is ZDDP, which has been known to shorten catalytic converter life. Manufacturers have been redesigning engines for the last decade to minimize the need for ZDDP, in order to lower emission levels. One method is switching over to roller rockers.

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Why not just use diesel rated oils, since they contain higher levels of ZDDP?

      Diesel engine requirements are much different that those of gasoline engines. The higher speeds and lower bearing surface-to-power ratios of gasoline engines require oil with higher shear ratings than most diesel oils. Diesels also have higher bearing clearances and that calls for higher viscosity oils. The additional detergents required for soot control actually reduce the effectiveness of added levels of ZDDP found in diesel oils. Also, newer diesel oils beginning in 2007 have greatly reduced their content of ZDDP.

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How does ZDDPlus™ compare to EOS?

     Historically, EOS was the most concentrated ZDDP supplement available. It was intended to boost ZDDP levels of oils that already contained EP additives. EOS was packaged in a 16 oz bottle. It also sold for over $10 per bottle. ZDDPlus™ is packaged in a 4 oz bottle and contains TWICE the amount of ZDDP contained in EOS, since it is intended to be used with newer oils that contain little or no ZDDP. In the summer of 2007, EOS was discontinued, making it difficult to find today.

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What about the additives offered by the cam manufacturers?

     Some of the "Break-in" or "assembly lubes" offered by cam manufacturers contain marginal amounts of ZDDP while others offer virtually none. In most cases these products are intended for initial run-in and rely primarily on other additives such as MDS (molybdenum disulfide). These products are seldom recommended for continued use and most are intended to be removed before the engines are put into service.

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What about off-the-shelf oil additives?

     Automotive engines have always been designed and warranted to work properly with the current available oil at the time of manufacture. There has not been a single off-the-shelf additive shown to perform any beneficial function except financial gain to the additive seller. Unlike other additives that have never been recommended by manufacturers, ZDDPlus™ is a replacement for the long-used component of oil that manufacturers once required, but over the years have been forced to remove from the oil for the benefit of newer cars at the expense of older cars.

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What about the claims of the various additives?

     The performance record of ZDDP is well established. We make virtually no claims for ZDDPlus™ , EXCEPT that it restores the EP (extreme pressure) function of the oil to the level originally required for your older car. Other additives make claims so ludicrous; they cannot be accepted based on common sense. If the claims attributed to most additives were even partially true they would have been part of the standard crankcase fill directly from the manufacturers like ZDDP has been for decades.

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Where can I learn more about ZDDP?

     A quick search of Yahoo or Google will immediately provide one with numerous sites that deal with this subject. Most sites are credible although many date back several years to a time when things were not as critical as they are now in 2008.

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