Synthetic Oil Information
Thought I'd pass along some interesting information on synthetic oil from a newsletter I receive from a local BMW motorcycle shop...
Synthetic Oils
Snake or Miracle Oil?
You might be surprised to hear us referring to “synthetic oil” as “snake oil.” We have used synthetics since day one and switched completely to synthetics in 1993 when BMW endorsed their use. Thirteen years and tens of thousands of quarts of synthetic oil later, why then the sudden change? Because the name “synthetic oil” itself is not a true indicator of a premium quality product. Let’s dig a little deeper to understand why.
Group III and IV Base Stocks
The current definition of “synthetic oil” for labeling purposes includes Group III and Group IV base stocks. In simple terms, Group III is Group II conventional crude oil that undergoes additional processing. Group IV on the other hand is engineered oil built at the molecular level to produce a completely uniform base stock. We simply don’t believe crude oil refined extra steps qualifies as synthetic or that it will provide anywhere near the same level of protection.
Maybe you’re just jumping to conclusions here. Surely a respected scientific community made the determination that Group III oils were just as good as Group IV to be called synthetics! No. Ok, then it must have been an engineering community that could have proven the virtues of one against the other through comprehensive testing. Wrong again! The fact is that there is no definition offered by any respected scientific or engineering community defining what constitutes “synthetic oil.”
Ok, then who could have made such an important decision? Would you believe the National Advertising Division (NAD) of the Council of Better Business Bureaus? Why on earth would the NAD get involved in deciding what constitutes synthetic oil? It’s simple; in 1997 Castrol changed the base stock in their Syntec product line from Group IV to Group III. Complaints were filed against Castrol for continuing to call their product synthetic oil. Without any scientific or engineering definitions, the NAD took it upon themselves to make the determination. Since Group III is Group II processes through extra steps, the NAD felt it was a reasonable basis for the claim that Castrol Syntec was synthesized.
Since this momentous decision, a number of other companies have followed suit switching their synthetic products to Group III base stock. Most these products are still sold at a premium price level since consumers are willing to pay more for synthetics. The problem is that consumers are paying more because they believe they are getting a substantially better product! I believe people are buying “snake oil” they think is better due to a ruling by the NAD.
Group III vs. Group IV
Wait a minute, in testing Group III oils test almost as good as Group IV. Wouldn’t this be an indicator that Group III oils are just as good?
If you bought a new car you more than likely noticed the estimated fuel averages for city and highway driving. Like most of us, you probably haven’t seen that mileage other then on the sticker. Several factors affect your actual mileage including individual driving styles, engine break-in, gas quality, weather, road surface, etc. We all know these facts and realize these estimates are simply standardized measurements that allow us to compare different vehicles tested under the same conditions. It doesn’t mean we should expect that level of performance.
In a similar manner, oils are tested using an assortment of standardized tests. Oils can be compared against each other based on test results, chemical makeup and additives. In the real world, these oils are used in a wide variety of operating conditions and exposed to a number of contaminates including condensation, exhaust blow by and air particulate. Not to mention environmental conditions, vehicle maintenance and individual driver demand. All of these variables combined place unique demands on your oils. Here too, real world performance varies from the test environment.
We have first hand experience with the results of 3,000-6,000 miles of use on oils in the real world heat and humidity of Florida on a modern clean burning engine. Conventional oils are pushed to and in some cases beyond their limits. We were not surprised to see these oils breakdown under these conditions. What did surprise us was the poor performance of some synthetic oils.
Our records show which specific oil or oils were used in each and every service. We also ask new customers or those that do their own service what oils they use and when they last changed it when we find sludge for example in their motor.
Could the oil be breaking down because they are running it well beyond the recommended limits?
Is it a case that they are simply using low grade oils?
Almost everyone was following BMW's mileage and/or time recommendations for their oil changes. All the oils that performed poorly were either Group II or the "so called" synthetic Group III base stock oils!
Group IV Advantage
Crude oil is comprised of a wide range of different size molecules. The size of individual molecules ultimately determines the thickness or viscosity of the oil. The larger the molecule size, the thicker the oil. For engine oils, a medium sized molecule yields the desired fluid viscosity. Crude oil is refined to remove unwanted molecules. However, the resulting Group II and III products are still comprised of a cocktail of various size molecules.
In hot engines the smaller molecules evaporate which is generally perceived as oil consumption. Of greater concern is the fact that the remaining oil is thickening as a direct result of losing the smaller molecules. Larger molecules tend to have weaker bonds that break or sheer. Gears in motorcycle engines not typically found in automotive applications contribute to molecular sheer. The broken molecules bond with free oxygen or other free molecules growing into very large molecules forming sludge that further increases oil viscosity.
Group IV base stock oils are comprised of molecules that are all exactly the same size. These molecules are engineered to provide the desired viscosity and a very strong molecular bond. As a result, there are no small molecules to evaporate and molecules are highly resistant to breaking or shearing. Therefore, these oils are highly resistant to forming sludge or viscosity changes. Group IV oils hold up better in higher temperatures under all conditions.
Bottom Line
Now to answer the question regarding which oil type and approach is better.
Conventional oil (Group II or III) changed more frequently than the recommended interval.
Synthetics oil (Group IV) changed at the vehicle manufacturers recommended interval.
The fact is that a Group IV synthetic is the only way to go. Conventional oils do not hold up well in our experience even when changed at three times the recommended interval. If you calculate the just cost of the oil, filters and gaskets alone, it costs more. Then there's the issue of disposing of the waste oil and filter. These items are controlled substances in the State of Florida regulated by the Environmental Protection Agency (EPA).
Our first hand experience has shown that engineered Group IV synthetic base stock oils are still going strong at 6,000 miles. What happens if you're on the road traveling or something comes up and you accidentally run past the recommended change interval? Which oil would you rather have in the crankcase? Why put yourself through the extra work and expense of conventional oils. Do the job right and ride with confidence between services.
Just be on the look out for "snake oil" disguised as synthetic. You want to be sure you’re getting Group IV PAO base stock oils for your motor and driveline.
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