Tech article by Todd Henderson (74bronc)

If you're like me, the idea of religious 3,000 mile oil changes has been crammed into your being ever since you began learning about cars. This philosophy is undoubtedly a result of decades of 3,000 mile oil/filter changes and the "Quick Change" oil establishments that continue to promote this mentality. While oils of the past and some modern oils need to be changed frequently, today's oil technology has changed so much that the 3,000 mile oil change should be completely forgotten.

During the last few decades, more effective ways to maintain modern automobiles have been proven using modern lubricant technology. Why do we still insist upon changing our oil so frequently? It's because most of us still use petroleum-based oils in our gasoline and diesel engines. These oils are prone to speedy breakdown because of the harsh environment that they live and labor in. As all of their additives are used up and as their molecular structure is broken down, they become less capable of doing their job effectively. Old-school car fanatics and some uninformed mechanics will still tell you that you HAVE to religiously change your oil every 3,000 miles in order to avoid catastrophic engine failures. The fact of the matter is that even car manufacturers are recommending much longer oil change intervals than they used to.

For example, my 1996 Honda Civic has a recommended oil change interval of 7500 miles, the 2002 Cadillac Seville has a 12,500 mile interval, the 2001 LS-6 Corvette has a 15,000 mile change interval, Porsche recommends a 15,000 mile interval and all new BMW's use a computer to calculate when the oil should be changed and the interval usually comes out to 10-15,000 miles. A myriad of other car companies have also raised the recommended oil service interval significantly in new production vehicles and much of this is due to the introduction of synthetic lubricants. While it is perfectly okay to follow the old school of thought and flush your money and time down the toilet by doing frequent oil changes, you have another option.
Synthetic lubricants have been around for decades but they have not been widely accepted or used in the automotive industry until recently. Synthetic motor oil was first introduced to the automotive industry in 1972 when Lt.Col. Albert Amatuzio, a jet fighter squadron commander, used jet engine synthetic oil technology to develop a fully synthetic motor oil that exceeded API specifications for use in motor vehicle engines. Amsoil Inc. was born and has been supplying top quality synthetic lubricants to racers and automotive enthusiasts ever since. Mobil Oil Company released its version of a fully synthetic motor oil in 1975 (Mobil 1) but their product didn't become popular until the 90's as a result of an aggressive marketing campaign. Many other top quality fully-synthetic motor oils are available now including Redline, NEO and Royal Purple. Even the major oil companies have jumped on the synthetic bandwagon by releasing their versions of synthetic products such as Castrol Syntec, Valvoline SynPower, Quaker State Full Synthetic, Pennzoil Synthetic with Pennzane, Exxon SuperFlo Synthetic and others. Some of these products are marketed as "synthetic" oils, but in reality, the definition of "synthetic" was changed to better meet certain companies' definition of "synthetic", which differs from what a true synthetic motor oil really is. When choosing a synthetic motor oil for your engine, you need to make sure that it is a true synthetic and not a re-defined, reformulated petroleum product, which will not protect your engine as well as a pure synthetic motor oil will.

So why don't more people use synthetic motor oil? The answer is because of price and misinformation. I believe that synthetic motor oils will be the lubricant of choice in the future for a variety of reasons. The benefits of synthetics far outweigh those of petroleum motor oils. You will be hard pressed to find anything negative said about synthetic motor oils anywhere because most people agree that they are superior in every way to their dinosaur-based competition. While the initial cost of investing in synthetics for your vehicle may seem a little high to begin with, you must first understand the long-term benefits of changing over to and sticking with synthetics.

Amsoil was the first company to introduce the term "extended interval" oil changes, which means that they did away with the 3-5K mile oil change interval mentality. Through thorough research and testing, Amsoil discovered that synthetic oils resist the breakdowns commonly associated with petroleum based oils which allows synthetics to be in service much longer than petroleum oil. Their research indicated that it is possible to go up to a 25K mile change interval in an automotive engine or even longer with the proper filtration setup installed on the engine. This is done while retaining a consistent oil filter change interval but still using the same oil in the crankcase. By replacing the filter and topping off the crankcase, you reintroduce the additives that are used up over the course of the filter change interval, rendering the oil useable for many more thousands of miles. The only way to really tell if oil has destructed to the point of being unusable is to do an oil analysis, a common practice in the trucking and aviation industries. This independent laboratory test determines which additives are still present in the oil and decides if the oil can continue to be used. Oil analysis companies report the facts surrounding the oil without a hidden agenda. This means that your oil is either suitable for continued use or it's not.
Oil manufacturers enjoy the 3K mile oil change mindset of the American public because it continues to provide them with job security. If oil change intervals significantly increased in duration, much less motor oil would be required which would directly affect the oil companies that manufacture petroleum motor oil. If top quality synthetic motor oil is used with a good filtration system, we would virtually eliminate mechanical wear in engines and other components, obviously making automobiles last much longer.

Benefits of Synthetic Motor Oil

Much of the technology that we have in the automotive industry is derived from the aviation industry because of the demand for perfection and durability in aviation. Aviation engines have to be as reliable as mechanically possible because there is no easy way to pull over and investigate a problem when you are miles up in the sky. Automotive synthetic oil was created from jet engine oil technology, which means that automotive synthetics are based on oils that have proven themselves in the toughest of conditions in jet engines over many years of reliable service. There are many benefits to using synthetic lubricants in your classic ride and most are summed up as follows:
  1. Synthetics stand up to heat and breakdown much better than conventional oils (engine stays cleaner on the inside)
  2. Synthetics have the ability to flow at incredibly low temperatures which better protects the engine on startup in cold climates
  3. Synthetics lubricate much better than conventional oils because of their molecular structure
  4. Synthetics tend to cling to metal parts better than conventional oils which means they help protect the engine on startup
  5. Because of their added slipperiness, synthetics help improve gas mileage, HP and torque
  6. Synthetics are home grown which means dependence on Middle Eastern Oil is lowered
  7. More environmentally friendly than petroleum based products
  8. Longer change intervals which offsets the additional cost of Synthetic
  9. Help the engine to run cooler
  10. Higher film strength which keeps metal-to-metal contact to a minimum

1. Synthetics stand up to heat and breakdown much better than conventional 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 degrees) compared to conventional oil, which begins vaporizing at temps as low as 350 deg. F." (Muscle Mustangs and Fast Fords) While any knowledgeable enthusiast will know that the oil temps in an internal combustion engine will never get than high, the oil is constantly exposed to these kinds of temperatures in the cylinders near where the combustion is occurring. This exposure is what breaks down conventional oils as the oil vaporizes. As conventional oils vaporize, they create sludge and varnish on the inside of the engine. If left unchecked, this sludge and varnish can create a host of problems including higher oil temps, increased oil consumption and decreased oil flow to critical engine components.

2. Synthetics have the ability to flow at unbelievably low temps- This is one of the reasons that synthetics were developed in the first place. As early as World War II, synthetics were used in equipment in extremely cold temperatures as a way to speed up oil delivery to critical components. As most of us know (because of marketing tactics by modern snake oil manufacturers i.e. Slick 50), most wear in an engine occurs on startup when the oil is in the pan. This wear occurs as a result of the brief metal-to-metal contact as the oil slowly makes its way through the oil system. Synthetics have a much better flow rate at cold temperatures making them ideal for critical protection in cold climates. The faster you can get the oil flowing through the engine, the more protection the oil will be able to render.

3. Synthetics lubricate much better than conventional oils because of their molecular structure- The molecules of petroleum lubricants are jagged, different sizes and different shapes. The molecular structure of synthetic lubricants includes molecules that are uniformly shaped and sized. Because of this molecular structure, the synthetic molecules slide past each other creating far superior lubricating ability. We all know and understand that less resistance and friction causes less wear, less heat and better flow which in turn results in more horsepower/torque and better gas mileage.

4. Synthetics tend to cling to metal parts better than conventional oils which means they help protect the engine on startup- Mineral-based oil drops off of internal engine components and rests in the oil pan until the engine is started again, leaving unprotected metal surfaces for startup. Synthetic lubricants cling to the engine components and create a film that doesn't completely drip off. While it is an unscientific test, buy a bottle of synthetic motor oil, pour it into the engine until you can't get anymore out of the bottle, put the bottle right side up again and wait a few hours. Upon re-inspection, there will be a significant amount of oil in the bottom of the bottle from the oil that was clinging to the sides of the bottle.

5. Because of their added slipperiness, synthetics help improve gas mileage, HP and torque- One job of motor oil is to counter the friction that is found inside an internal combustion engine. If this friction can be still lessened using synthetic motor oils, the obvious benefits are going to be less heat and more power. If the engine doesn't have to work as hard just to run, more power will be available to propel the vehicle.

6. Synthetics are home brewed, which means dependence on Middle Eastern Oil is lowered- This is an obvious benefit of synthetic lubricants. As we use more and more synthetics, we are not as dependent on oil that is formulated out of mineral-based oils, especially from the crude oil that comes from the Middle East.

7. Longer change intervals which offsets the additional cost of Synthetic - Because synthetics resist the common breakdown associated with petroleum motor oils, it is not necessary to change synthetic motor oil as often as petroleum motor oil. People still religiously believe that motor oil should be changed every 3K miles but they fail to recognize that OEM change intervals are steadily rising. The expense of synthetic motor oil can easily be offset by the extended drain interval. It is a win win situation for synthetics.

8. Help the engine to run cooler - Roy Howell of Redline Synthetic Motor Oil Co. says "Synthetic oil has 10% better heat transfer than Petroleum based lubricants." What this translates into is that synthetic oil does a better job of dissipating heat in an engine than petroleum based oils. This allows the engine to run cooler overall. Oil temps have been proven to run up to 50 degrees cooler with synthetic oils. The following is taken from an article titled "Synthetic Oil: Rx For Long Engine Life" by Curt Scott. "The remarkable ability of synthetic oils to reduce internal operating temperatures is far too important to ignore, since high operating temperatures contribute directly to premature failure of mechanical components and gaskets and seals. Coolant cools only the upper regions of an engine. The task of cooling the crankshaft, main and connecting rod bearings, timing gear and chain, the camshaft and its bearings and numerous other components must be borne entirely by the oil. There are three identifiable reasons why synthetics do a better job of cooling an engine. 1. Because both the oil's lubricity (slipperiness) and it's stable viscosity, less friction and thus less heat is generated in the first place. 2. The molecular structure of the oil itself is designed to more efficiently transfer heat, even compared against the thermal conductivity properties (ability to absorb and dissipate heat) of an identical viscosity. 3. As mentioned in the preceding paragraph, the more rapid oil flow of these lower-viscosity synthetics contributes significantly to the efficient transfer and dissipation of heat.

Because of all these factors, oil temperature decreases of from 20-50 degrees are quite common with the use of synthetic oil. One might even say that the heat-reduction properties of synthetics are synergistic…by helping to reduce its own temperature, the synthetic oil is simultaneously enhancing the lubricant's overall performance characteristics."

Synthetic Oil Myths

During the early development and formulation period of synthetic motor oils, certain additives and techniques were used which made synthetics incompatible with some seals found in motor vehicle engines. There was also a question of whether or not synthetics could be reliably mixed with conventional oils. Because of these facts, synthetics received a bad reputation, which has caused modern synthetic manufacturers to have to re-educate people about their products. There are also many other myths floating around about synthetic lubricants and some clarification is needed. The following was written by Ed Newman and published in National Oil & Lube News. Mr. Newman effectively sets the record straight on many common synthetic misconceptions.

1. Synthetic motor oils damage seals - Untrue. It would be foolhardy for lubricant manufacturers to build a product that is incompatible with seals. The composition of seals presents problems that both petroleum oils and synthetics must overcome. Made from elastomers, seals are inherently difficult to standardize. Ultimately it is the additive mix in the oil that counts. Additives to control seal swell, shrinkage and hardening are required, whether it be a synthetic or petroleum product that is being produced.

2. Synthetics are too thin to stay inside the engine - Untrue. In order for a lubricant to be classified in any SAE grade (10W-30, 10W-40 etc.) it has to meet certain guidelines with regard to viscosity (thickness). For example, it makes no difference whether it is 10W-40 petroleum or 10W-40 synthetic, at –25 Degrees centigrade (-13F) and 100 degrees centigrade (212F), that oil has to maintain a standardized viscosity or it can't be rated as 10W-40.

3. Synthetics cause cars to use more oil - Untrue. Synthetic motor oils are intended to be used in mechanically sound engines, that is, engines that don't leak. In such engines, oil consumption will actually be reduced. First, because of the lower volatility of synlubes. Second, because of the better sealing characteristics between piston rings and cylinder walls. And finally, because of the superior oxidation stability (i.e. resistance of synthetics against reacting with oxygen at high temperatures).

4. Synthetic lubricants are not compatible with petroleum products - Untrue. The synthesized hydrocarbons, polyalphaolefins, diesters and other materials that form the base stocks of high quality name brand synthetics are fully compatible with petroleum oils. In the old days, some companies used untested ingredients that were not compatible, causing quality synlubes to suffer a bum rap. Fortunately, those days are long gone. Compatibility is something to keep in mind, however, whether using petroleum oils or synthetics. It is usually best to use the same oil for topping off that you have been running in the engine. That is, it is preferable to not mix your oils, even if it is Valvoline or Quaker State you are using. The fact is this: the functions of additives blended for specific characteristics can be offset when oils with different additive packages are put together. For optimal performance, it is better to use the same oil throughout.

5. Synthetic lubricants are not readily available - Untrue. This may have been the case two decades ago when Amsoil and Mobil 1 were the only real choices, but today nearly every major oil company has added a synthetic product to their lines. This in itself is a testament to the value synthetics offer. But, beware, many of the other "synthetics" are not true PAO (Polyalphaolefin) synthetics (i.e. Castrol Syntec, Pennzoil etc.). They are hydroisomerized petroleum oil or an ester based synthetic blend.

6. Synthetic lubricants produce sludge - Untrue. In point of fact, synthetic motor oils are more sludge resistant that their petroleum counterparts, resisting the effects of high temperatures and oxidation. In the presence of high temperatures, two things happen. First, an oil's lighter ingredients boil off, making the oil thicker. Second, many of the complex chemicals found naturally in petroleum basestocks begin to react with each other, forming sludges, gums and varnishes. One result is a loss of fluidity at low temperatures, slowing the timely flow of oil to the engine for vital engine protection. Further negative effects of thickened oil include the restriction of oil flow to critical areas, greater wear and loss of fuel economy. Because of their higher flashpoints, and their ability to withstand evaporation loss and oxidation, synthetics are much more resistant to sludge development. Two other causes of sludge-ingested dirt and water dilution- can be a problem in any kind of oil, whether petroleum or synthetic. These are problems with the air filtration system and cooing system respectively, not the oil.

7. Synthetics can't be used with catalytic converters or oxygen sensors - Untrue. There is no difference between synthetic and petroleum oils in regards to these components. Both synthetic and petroleum oils are compounds and neither is damaging to catalytic converters or oxygen sensors.

8. Synthetics void warranties - Untrue. No major manufacturer or automobiles specifically bans the use of synthetic lubricants. In point of fact, increasing numbers of high performance cars are arriving on the showroom floors with synthetic motor oils as factory fill. New vehicle warranties are based upon the use of oils meeting specific API Service Classifications (for example SG/CE). Synthetic lubricants, which meet current API Service requirements, are perfectly suited for use in any vehicle without affecting the validity of the new car warranty. In point of fact, in the over 25 years that Amsoil Synthetic Lubricants have been used in extended service situations, over billions of miles of actual driving, these oils have not been faulted once for voiding an automaker's warranty.

9. Synthetics last forever - Untrue. Although some experts feel that synthetic basestocks themselves can be used forever, it is well known that eventually the additives will falter and cause the oil to require changing. Moisture, fuel dilution and acids (the by products of combustion) tend to use up additives in an oil, allowing degradation to occur. However, by "topping off", additives can be replenished. Through good filtration and periodic oil analysis, synthetic motor oils protect an engine for lengths of time far beyond the capability of non-synthetics.

10. Synthetics are too expensive - Untrue. Tests and experience have proven that synthetics can greatly extend drain intervals, provide better fuel economy, reduce engine wear and enable vehicles to operate with greater reliability. All these elements combine to make synthetic engine oils more economical than conventional non-synthetics. In Europe, synthetics have enjoyed increasing acceptance as car buyers look first to performance and long-term value rather than initial price. As more sophisticated technology places greater demands on today's motor oils, we will no doubt see an increasing re-evaluation of oil buying habits in this country as well.

Arguments Against Synthetics

The most common argument that I hear about synthetics sounds something like this: "I have been using petroleum oils for years, changing my oil religiously at 3K miles and I have never had an engine related problem." While this may be true, why go through the hassle of changing the oil unnecessarily every 4 months or 3K miles? In a world where there are so many things competing for our time, many people welcome the chance to allow their oil to remain in the crankcase for 1 year without having to give it a second thought. Not only do they have the assurance that it is doing a much better job than petroleum oil, they don't have to worry about changing it out as often.

Another common argument I hear sounds something like this: I change my oil religiously at 3K miles and use only petroleum oil, but when I took the heads off, I could still see original hone marks in the cylinder walls. For every comment like this that I have heard, I have come across many situations where people are doing costly engine overhauls or component replacement due to worn out parts regardless of their maintenance schedule. Recently I talked to a gentleman who had his truck at a dealership to do a recall on the cylinder heads and was informed that there were nasty ridges at the tops of his cylinders and it would cost him close to 3K to overhaul the bottom end of the engine. This engine was meticulously maintained with petroleum oil and had well under 100K miles on it. Did the oil cause this? That is hard to say. Was the owner of this 1995 pickup bummed to have to be thinking about an engine overhaul? Yep!!

Any time an owner is planning to keep a vehicle for many years, I always recommend a synthetic oil. While a petroleum based oil may be adequate, I demand the best for my vehicles. I plan to keep my vehicles for many years and hundreds of thousands of miles and that is why I use synthetic lubricants. Could I go 200K on a vehicle using petroleum oil? I am sure I could but I am also sure that I could go 400K on the same engine using synthetic oils.


Whether or not you decide to switch over to synthetics will depend on whether or not you see or can feel a difference in the way your vehicle runs to justify the cost of synthetic oils or if you feel that the other characteristics of synthetics are worth spending the extra money. I am a firm believer in the benefits of synthetics and I would much rather pay a little extra for a lubricant that I can put in and not have to worry about changing for an extended period of time. I also have the knowledge that the synthetic is doing a better job at lubricating than any other lubricant which means I won't have to worry about costly overhauls as often as I would with other lubricants. Synthetic lubricants are easily accessible at auto parts stores or online parts houses. Independent product testing proves synthetics to be, in every way, superior to any kind of petroleum lubricant. The only thing that you need to decide is if it is worth the money to you to protect your costly investments.

* I have no affiliation with Amsoil, Inc. I use their products along with other top quality synthetic products. The information found in this article was current as of 11/02 but because of the changing nature of automotive products, it may not be as current at the time you read it. There is ample information on the world wide web about synthetic lubricants and I encourage you to do some of your own research before making a decision on which oil to use in your vehicle. If you want to contact me directly, I welcome any correspondence via email at