Synthetics: The Auto Industry’s Best-Kept Secret

Base article is from Muscle Mustangs and Fast Fords Magazine, with additional commentary by Performance Oil Technology, L.L.C.

Have you ever heard the story about the light bulb that doesn’t burn out or the razor that never dulls? Sure, these stories get exaggerated, but sometimes there’s an element of truth to the rumors leaking out of a manufacturers skunk works. One particular rumor that sounds too good to be true is “an experimental motor oil that increases horsepower, practically stops internal engine wear in its tracks and improves fuel efficiency.”

Well, synthetic motor oil is not a rumor. It’s been in use ever since World War II (the Germans used it on the cold eastern front because conventional oil wouldn’t flow in the arctic-like weather). Even though it sounds too good to be true, synthetics do reduce engine wear, improve gas mileage and increase horsepower. This is because synthetic oil molecules are superior in a number of ways to mineral-based oils

Synthetic Oil is Superior to Mineral-Based Oil in Every Way:

Without getting too technical, suffice it to say that synthetics have a much higher resistance to heat than mineral-based oils. Because synthetic oil is composed of molecules that are uniform in weight and shape, its heat of vaporization is much higher (more than 600 deg. F.) compared to conventional oil, which begins evaporating at temps as low as 350 deg. F. This added stability at high temperature means that your hard-working engine wont burn up as much oil- and that means less sludge and fewer varnish deposits in the engine.

Added lubricity is another attribute of synthetics. The uniform diameter of synthetic oil polymers allows them to more easily slide over one another. The resultant reduction in friction shows up as more horsepower and torque and reduced internal engine wear.

Higher film strength, however is one of the major benefits of synthetics. Film strength is what keeps oil molecules from being pushed away from each other under pressure. Mineral based oil has a film strength of about 400 psi, while synthetics usually exceed 3000  psi. In an area where two metal surfaces meet, the film of oil between them prevents them from rubbing and wearing away at each other. Synthetics do a better job of this than conventional mineral oils. It takes more than seven times as much pressure to squeeze synthetic oil from between two surfaces than mineral-based oil. Consequently, synthetics are much better at keeping your engine like new.

Not All Synthetics Are Created Equal:

Please be aware that not all synthetics are created equal. There is wide differences in quality and protection provided by the various synthetics. Additionally, not all synthetics are 100% synthetic. Many are partial synthetics marketed under the perception of full synthetics to the unsuspecting consumer or even hydrocracked oils such as Castrol Syntec, for example, which is a hydroisomerized petroleum oil marketed under the disguise of a synthetic. There are no PAO (polyalphaolefins) synthetic molecules in Castrol Syntec,  yet because of  legal finagling with the definition of  synthesized motor oils they can legally be called synthetic. Basically, they changed the definition of a synthetic to fit their process of highly refining a petroleum base oil, called hydrocracking and fought with Mobil and the National Advertising Council to loosen the definition of a synthetic. 

Film strength is important in another way- cold start protection. Regular mineral-based oil will not remain as a boundary layer (a uniform thin coating) on metal surfaces when an engine is turned off. Mineral-based oil drains off parts and out of passageways into the oil pan. Additionally, mineral-based oils contain waxes and paraffin's that come out of the earth and solidify when it gets colder outside, therefore making it even harder to pump the oil when cold. When you crank your vehicle the metal surfaces (crankshaft, camshaft, lifters, connecting rod bearings, piston pin bushings & bearings, piston, rings and cylinder walls) that require lubrication are not fully lubricated in the time it takes for the oil pump to pressurize the lubrication system and supply oil to the engine.

With Mineral-Based Oil Your Engine is Not As Well Protected During One of The Most Critical Times: Engine Start-Up:

Engine start-up lubrication is one of the most critical times for lubrication. Small amounts of wear occurs every time you start your engine with mineral-based oils. Over time, these small amounts of wear add up to larger amounts and result in increase clearances, reduced oil pressure, increase oil consumption and reduced life of your engine. Synthetic motor oil, on the other hand, will stay on engine parts and coat them uniformly because of its high film strength and greater heat affinity (it adheres better to hot metal parts). Additionally, synthetics prevent start-up engine wear and are pumped to critical passageways, surfaces and bearings much faster than mineral-based oils. With mineral-based oils your engine is basically running with no oil (which can be as much as 20-30 seconds, depending on the severity of cold weather, after cranking the motor). With synthetics after several hundred thousand miles you still will have a strong running engine, instead of a used-up engine that may require a re-build. 

Okay. Synthetics are great. The real question is: Why doesn’t everybody use them? Manufacturers don’t use synthetics in production vehicles (except as where needed to prevent component failure during the warranty period) for at least two reasons. It is our opinion that they want to sell you a new vehicle more often,  and synthetic motor oil would significantly reduce their chances of doing that. A few auto companies install a synthetic oil as a factory fill in very high performance vehicles such as the Chevrolet Corvette, for example.

(additionally, it is our opinion that oil companies want to sell oil to keep their oil wells and refineries running and they do that by recommending the 3000 mile oil change. Sure, they all offer a synthetic or semi-synthetic now, but it is only a very small percentage of total oil sales volume. Basically, what you are seeing here is the oil and auto companies working together so they both benefit from the "3000 mile oil change").

(Many of the same oil companies that recommend 3000 mile oil changes in the U.S. also offer and recommend 12,000-18,000 mile oil changes in Europe, and have been for many years and have plans for increasing that to nearly 30,000 mile oil changes in the future. The technology is available yet  AMSOIL is the only one to offer a superior extended drain synthetic oil that far exceeds the performance specifications of any other type and brand of oil and back it with their own warranty).

AMSOIL Offers Extended Drain Intervals and Superior Filtration:

AMSOIL Synthetic Lubricants offers a 25,000 mile/1-year oil change, a 35,000 mile/1-year oil change with Ea Technology Filtration. Should the consumer choose AMSOIL By-Pass Filtration, this will allow for virtually no oil changes and filter down to 1/10 micron particle size.  The average consumer spending excessive amounts of time and money changing their oil every 3000 miles does not get the same level of performance and  protection as the AMSOIL customer that is saving both time and money and getting maximum performance, protection and extending the life of their engine and transmission (AMSOIL also offers synthetic extended drain interval transmission fluid that will virtually eliminate transmission wear and reduce operating temperatures approximately 20-50 deg. F., depending on operating conditions)

There Is A Good Use For Mineral Oil:

Please note that a new gasoline powered engine should be run on the factory fill mineral-based oil for about the first 500 miles and large diesel engines should be run about 5000-6000 miles in general before changing to synthetic oil. Mineral oil's lower shear strength can help promote easier engine wear-in, although you can convert to synthetic oil sooner if you like. Many production vehicles today come factory filled with synthetic oil. Engine break-in is not as critical today as it was in the old days. Material, engineering advances and manufacturing technology has improved drastically from the days when long break-in periods were required.

It is good practice to perform the first oil and filter change at 500 miles because the the initial change contains the highest wear metal content in the used oil and filter. The added friction and surface abrasion that mineral-based oils provide actually helps to seat the valves and create even mating surfaces between parts during the first several hundred miles (such as piston rings and cylinder walls). This is a time in the engine’s life that generates a high level of metal, aluminum, copper and some lead particles in the oil (that cannot all be caught by the filter). Again, you are perfectly ok to use synthetic oils sooner if you choose to (with the exception of 2-cycle engines). Your engine will still wear-in properly although it may take just a short time longer as compared to petroleum oil.

Major racing teams don’t appear to use synthetics, but things aren’t always what they seem. The racing team’s sponsor might want you to believe there’s a certain kind of motor oil in the car’s crankcase, but every successful race team in the world uses synthetic lubricants throughout the car and about 85% of them use AMSOIL.  Your probably wondering how we know these facts. It's simple: we work in the automotive industry with many professionals involved in the racing industry.  

Interestingly enough, the biggest reason that synthetic lubricants are not in widespread use is because the would-be consumer does not know of the benefits provided by synthetics.  Also, they are not sure where to go to ask or who to ask. Asking your local parts counterman at the auto parts or the high school kid at the quick-lube shop is not the answer, or even asking your local auto dealer that sold you the car- remember, they are usually tied in with the manufacturers brand or oil and the 3000 mile oil change myth.  You should seek out and acquire information from a Certified Lubrication Specialist, lubrication engineer or unbiased automotive engineer or competent mechanic that fully understands and can explain the benefits of synthetics and the drawbacks of mineral-based oil to the consumer. But beware, there are many mechanics out there that are so engrained in the old way of thinking that they refuse to change their way of thinking or even open up their minds to the fact that there are automotive engineers, lubrication engineers and chemists that know a heck of a lot more about motor oils, filtration, vehicles and synthetics than them.

Some People Will Never Change:

Also, even though people have known about synthetics for years, consumers continue to be brand and price driven. The rationale continues to be, “My grandpappy used brand V in his model T, so I won’t use nothing else.” Or, “I been using brand Q in my IROC for years. If I change brands now I’ll blow the motor.” Or, “ I ain’t payin’ no five dollars a quart, no siree, Bob, I ain’t that stupid.” Or, “I ain’t using none of that synthetic oil...that’s stuff’s made out of beans...I want some real crude oil.” (this last statement was an actual statement from a customer in a snowmobile store. He was having 2-cycle spark plug fouling problems due to the mineral- based oil mixture he was using. The store suggested he use a synthetic oil and 2 new spark plugs to eliminate the fouling issue. He declined and purchased 2 boxes of spark plugs and his usual crude oil mix ; guess some people will never change).

Synthetics Are Compatible With Mineral Based Oils, But Be Careful:

When switching to a synthetic motor oil, it is important to keep several things in mind regarding oil consumption. Keep extra quarts of synthetic handy. Although many synthetic oil manufacturers tout the compatibility of their oils with mineral-based oils, adding mineral oil to synthetic oil will drastically reduce the level of engine protection that was initially designed into the synthetic oil as well as the mileage to your next oil change.  Also, as the mineral oil breaks down it will contaminate the rest of the oil, leaving sludge and varnish deposits in the engine (this is because mineral oil is made up of many chemically dissimilar hydrocarbons, including waxes, all of which react differently under different operating conditions). By adding a mineral oil to synthetic oil you will also see a reduction in engine efficiency. depending on how much, and when, the mineral-based oil was introduced.

There are many different companies that offer synthetics. because this overview is intended to give readers a general idea of the benefits of synthetic lubricants, we have not discussed the specific differences between all the individual brands and their formulations. Keep in mind that there are significant differences between brands of synthetics, which will affect the performance and longevity of your engine, transmission, axles, bearings and chassis components.