Aren’t the newer oils better than the older oils?
Historically, every new grade of oil introduced since the 1930s was better than the previous grade and could be considered “improved” with one exception. The original SA grade was straight mineral oil (non-detergent and without 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 newer cars, they are not better for older cars. Simply put, the newer and/or better oils are not backward compatible for older cars, primarily due to the gradual reduction of ZDDP starting with SG grade in 1988.
How much ZDDPlus™ should I add to my oil?
One bottle of ZDDPlus™ will raise the ZDDP level of SL or SM spec oil to the standards that were in place when SF (or earlier) oil was specified.
What if my oil already contains 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.
Can I use ZDDPlus™ with regular and synthetic oils?
ZDDPlus™ should be compatible with all conventional and synthetic oils intended for automotive use. Virtually all of these oils have contained higher amounts of ZDDP for years and only recently have the levels been decreased.
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. 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; however, the ZDDP can be restored by slowly heating to a temperature slightly above 100C.
When should ZDDPlus™ be added?
ZDDPlus™ can be added anytime, but the best time is whenever the oil is changed. A single 4 oz bottle ZDDPlus™ provides the proper concentration for a 4- to 5-quart oil change.
How long does ZDDPlus™ last?
Minute amounts of the ZDDP molecule in the ZDDPlus™ form a necessary sacrificial additive which becomes depleted upon use. ZDDPlus™ is designed to last the life of a normal oil change for your vehicle; however, attention should be given to the categories of service known as “normal” and “severe.” The severe category includes stop-and-go driving and short trips, and results in shortened service life. Not only is the service life of ZDDPlus™ decreased, many other oil additives suffer as well.
Why should ZDDPlus™ not be used on 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.
Why not just use diesel rated oils since they contain higher levels of ZDDP?
Diesel engine requirements are much different than 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, which call for higher viscosity oils. The additional detergents required for soot control actually reduce the effectiveness of added levels of ZDDP found in diesel oils.
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. ZDDPlus™ is packaged in a 4 oz bottle and contains twice the amount of ZDDP than there is in a 16 oz bottle of EOS. Therefore, it takes two 16 oz bottles of EOS to equal the same concentration of ZDDP in one 4 oz bottle of ZDDPlus™. ZDDPlus™ is intended to be used with newer oils with little or no ZDDP. EOS was discontinued by General Motors in the second quarter of 2007.
What about the claims of the various additives?
We make virtually no claims for ZDDPlus™ except it restores the EP 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 alone. Consider, for example, fuel mileage. The only proven fuel mileage claim is that of the newer lower viscosity API rated energy conserving grades of oil which claim 1.5% for the Type 1 EC, and 2.7% for the Type II EC oils. Note - This claim is in percent, not mpg. If an additive was to actually boost fuel mileage 20% or more, then auto manufacturers would have found the very cheapest method possible to increase their CAFÉ fuel ratings! If there was any truth to these claims, virtually every car built would certainly leave the assembly line with those products installed!
Can an oil or additive have Zn and not P and still contain ZDDP?
It is important to note that the wear protection properties are due only to the characteristics of the ZDDP molecule and not to Zn or P in the oil in other forms or from other sources. This means that if a particular motor oil mentions the addition of Zn alone, or P alone, the ZDDP molecule is not present in that motor oil. The ratios of Zn and P can be manipulated by simply adding zinc salts or phosphates, but again, this does not produce ZDDP and has no anti-wearing action.
Lastly, depleted ZDDP releases Zn and P into the motor oil and testing for levels of either of these pure elements is not a gauge of the status of the ZDDP level. What does this mean? If you see an oil additive or motor oil specifying only a level of Zn without a level of P, then there is no ZDDP in that product.
