Oil Informational: LOTS of Info!

[Dominic Toretto]

There is too much confusion on oil here that it results in a new "What oil should I be using?" thread being generated about once a week. So what I have done is referred back to my old DSport Magazine for a VERY comprehensive write-up on synthetic oil technology.

Disclaimer: I did not research this information and give full credit to DSport Magazine for their research and information

Should I be using performance synthetic engine oil in my vehicle? If you are a reader of DSport, the simple answer is "yes." While additional cost of performance synthetic engine oil may seem out of line, the "actual" cost of use is generally much less. Let's say that you drive a vehicle that gets 20mpg and that you plan to change your oil every 3,500 miles. During 70,000 miles of driving, you will be changing the oil 20 times. Assuming the your engine holds 5 quarts of oil, you'll be purchasing 100 quarts of oil. If you purchase a quality conventional oil at $2.00 per quart versus a premium synthetic oil at $8.00 per quart, you may think that you saved $600 in the process. in fact, the savings are probably much less or you may even lose money. In one of our tests, we compared Mobil 1 synthetic oil to a leading conventional oil. In a non-modified 2005 G35, we experienced an increase in fuel mileage from 21mpg to 23mpg. This was an increase of 9.5 percent, which was considerably above the five percent mark we were expecting. Over 70,000 miles, our G35 will save 290 gallons in gasoline. Since we fill our tank with 91-octane fuel at $2.25 per gallon, we would save $652.50 in fuel costs. Hence, even if we paid $8.00 per quart for Mobil 1(we actually paid much less), we would have an extra $52.50 in our pocket after 70,000 miles. The bottom line is that the perceived additional cost of using premium synthetic motor oil may be quite different from the actual cost once fuel savings are factored.

In addition to saving fuel costs in the long run, there are other reasons that you need to run synthetic motor oil in place of its conventional counterpart. A premium synthetic engine oil has a superior base oil and, in nearly all cases, a superior additive package. Why? The answer is simple. It costs more, so the manufacturer can afford to use more expensive "ingredients" in the formulation. The superior base oil and additive package deliver increased horsepower, reduced engine wear and extended protection during extreme operating conditions. This can literally save thousands of dollars in cases where a conventional oil would fail to protect your engine.

The Base

All engine oils are made up of a base oil and an additive package. Conventional engine oils use a base oil that is derived through a conventional refining process. These oild fall into three different groups based on their purity level and their viscosity index. The Group I oils contain the highest level of impurities and the lowest viscosity index. Group II base oils have lower levels of impurities but, have the same range of viscosity index values. Group III base oils not only have a low impurity level like Group II oils but, they also have a superior viscosity index. Due to the fact that some high-quality Group II base oils (a.k.a. hydro-cracked) can have most of the performance characteristics of Group IV base oils, the National Advertising Department of the Better Business Bureau has allowed oils manufactured from Group III base stocks to be sold as "Synthetic." However, many companies in the performance lubrication industry still disagree with the ruling.

Group IV and V base oils are not solvent-refined base oils. Instead, these oils are polymerized base oils or "true" synthetics. both Group IV and V oils have a substantially higher manufacturing cost than Group III base oils. Group IV oils are also known as PAOs or Polyalphaolefins. Group V oils are non-PAO synthetics which are typically ester based. Compared to Group III oils, PAOs out perform in cold cranking performance simulators, have lower volatility and increased oxidation stability. What does that means to your engine? The end result is reduced engine wear, decreased oil consumption, and increased oil life. Group V base oils are typically diester(BDE) or polyol esters(POE). On a molecular level, the major difference between esters and PAOs are multiple ester linkages. The molecular linkages actually impart a polarity to the molecules. This polarity among the ester molecules actually enhances the physical properties of the fluid. At a given viscosity, ester-based oils will have the highest flash-point and lowest rates of evaporation. This makes these old very well suited for extreme temperature applications. However, Group V base oils also have the highest cost. Besides the higher cost for Group IV and Group V base oils, there is one additional consideration for performance oil manufacturers. PAOs tend to cause a shrinking tend to cause a shrinking in the elastomer seals in an engine while esters tend to cause a swelling of the elastomer seals in the engine. Many performance lubrication manufacturers use a combination of ester and PAO base oils to avoid elastomer seal issues. Other manufacturers address seal issues within the additive package.

Oil Performance Criteria
•Low Volatility
•High Film Strength
•High Viscosity Index
•High Lubricity
•High Detergency
•High Friction Reduction
•High Flash Point
•High Oxidation Resistance
•Low Foaming

Types of Base Stocks Summary

Group I - Lowest grade Solvent-refined base oil
Group II - Mid-grade solvent-refined base oil, lower impurity levels
Group III - Highest-grade solvent-refined base oil, improved viscosity index over Group II
Group IV - Poly-alpha Olefin "synthetic" oils
Group V - Non - PAO synthetics, generally diester or polyol esters based oils

The Additive Package

In doing research for this article we found that the percentage of additives varied from 10 to 25 percent of the finished product. According to Royal Purple, "Additive technology creates major differences between oils. For instance, mineral based oils with a superior additive technology can outperform a synthetic oil with mediocre additive technology." Torco expresses a similar opinion, "We believe there is too much focus on the base oil nowadays. The additive package is what protects against 97 percent of the friction that occurs in the upper cylinder and valve train."

Of all the companies responding to our questionnaire, Cosworth Performance Engineered Motor Oils provided the most thorough discussion of their additive package. Various detergents, dispersants, anti-wear additives, friction modifiers, viscosity-index improvers and anti-oxidants are employed to achieve a "dual-mode formulation strategy [that uses] one type of chemistry to handle moderate conditions and another [type of chemistry] for more severe."

Addititves are utilized to neutralize the acids that are the by-products of combustion. Other additives reduce the oils tendency to foam. Engine component protection is increased with anti-wear and anti-oxidant additives. Corrosion inhibitors and detergents reduce the formation of carbon and sludge buildup. Friction modifying additives allow for additional horsepower to be realized at the crankshaft while film-strength modifiers and viscosity-index improvers increase the oil's ability to protect under high-load and high-temperature conditions.

Types of Typical Additives
•Acid Neutralizers
•Anti-Foaming
•Anti-Oxidant
•Anti-Wear
•Corrosion Inhibitors
•Detergents
•Dispersants
•Film Strength Modifiers
•Friction Reducers
•Viscosity Improvers