Reinier Breytenbach

Aftermarket Oil Additives: What You Need To Know. How do you get the most bang for your car maintenance buck in the current, and very depressing economic climate? Do you skip regular servicing (a very bad idea), or do you rely on aftermarket oil additives to extend your oil replacement intervals? If you use additives, do you really know what you are putting into your engine? Do you really see the 20- to 30% fuel savings the manufacturers of some additives claim are possible because of reduced friction? These are valid questions, but an equally valid question revolves around how aftermarket oil additives stack up against regular engine oil in the real world. Manufacturers claim their products are nothing short of being “miracles in bottles”, while many lubrication engineers, chemists, and professional mechanics are of the opinion that most additives are nothing but harmful snake oil. Who to believe- or more to the point; why do car manufacturers NOT recommend the use of aftermarket oil additives if they are everything their manufacturers claim them to be? Read on, and we will explain some of the issues. What Is Regular Motor Oil? Regular oil, whether mineral or synthetic, is a complex mixture of base oil to which very precise amounts of additives are added to reduce friction, prevent sludge formation, and the formation of air bubbles as the oil is circulated through the engine. However, in the case of mineral oil, the base oil is derived from many different sources, which means that on a batch-by-batch basis, the base oil will react differently to additives, as well as the amount of additives required, because the chemical make-up of each batch of crude oil may be different from all others. The table below illustrates the differences in specific gravity, and thus, the composition of crude oil from different sources Crude Oil- California 60oF 0.918 Crude Oil- Mexican 60oF 0.976 Crude Oil- Texas 60oF 0.876 Typically, the additives used in regular motor oil include zinc dithiophosphate, phosphorous, and sulphur to act as corrosion inhibitors, friction modifiers, and detergents. Other additives include boron in various concentrations, as well as exotic salts in new, experimental formulations. In fact, the total volume of additives in any given volume of motor oil generally accounts for around 25% of the total, and the fact is that no modern engine can run without these additives. For instance, zinc, which is a super anti-friction agent, does not readily react with oil contaminants, which means that the zinc content of the oil is available to reduce friction and wear throughout the useful life of the oil. However, boron, which is also an excellent anti-wear agent, reacts to water in much the same way sulphur does, but in the case of sulphur, the combination of water and oxygen forms sulphuric acid, which has a pronounced negative effect on metals. Oil Drain Intervals On the whole, the formulation of modern engine lubricants provides the best possible protection against premature engine wear, but it is also true to say that engine wear cannot be eliminated altogether. Factors such as driving style, ambient temperatures, fuel quality and condition of the engine, maintenance schedules, and a host of others eventually cause a degradation of the oil to the point where it no longer provides the required level of protection- which brings us to aftermarket oil additives. The PTFE Saga Oil manufacturers go to great lengths to ensure their products perform consistently, and on the whole, they do. However, manufacturers of oil additives make ridiculous claims such as the “facts” that their products reduce engine wear by up to 80%, cause lower running temperatures, and best of all, that it is possible to run an engine across the width of America without oil, provided their product was used “correctly” in treating the oil before draining. The fact is that nobody knows for sure, (with the exception of Teflon) what is added to the normal base oil that constitutes the bulk of an additive. Several laboratories have run tests on aftermarket additives, and without exception, they all contained the exact same ingredients as normal oil, i.e., sulphur, zinc, and phosphorous compounds. However, almost all contained Teflon, a fluor polymer to which DuPont Chemical Corporation holds the patent. So where is the harm in that you may ask? The harm lays in the fact that in some cases, the “normal” additives are present in concentrations that inhibit, and in a few cases, renders the action of some additives useless. The same thing happens when normal motor oils are mixed because of incompatibility issues between certain additives. While there are “standard recipes” that make up all motor oils, almost all manufacturers include proprietary ingredients, or a combination of ingredients, that may not mix well with other brands. Nevertheless, very few drivers are chemical engineers, with the result that products containing PTFE powder quickly gained a huge following as the result of clever marketing and advertising campaigns by dozens of manufacturers of aftermarket oil additives. In efforts to prevent all and sundry making claims as to the benefits of Teflon as an ingredient in motor oil, the product specialist of Du Pont’s Fluor Polymers Division, J.F. Imbalzano, issued the following statement just over ten years ago- "Teflon is not useful as an ingredient in oil additives or oils used for internal combustion engines." Which statement is about as damning of the benefits of Teflon in oil as can be made. Teflon and the Law Long story short, the manufactures of aftermarket additives started howling that since Du Pont could show no conclusive proof that Teflon caused demonstrable harm to internal combustion engines, they are guilty of “restraint of trade”, which means that you cannot refuse to sell a product to someone merely because they might use for a purpose other than the one you envisioned for it. Predictably, the decision went against Du Pont, who now had no choice but to again supply additive manufacturers with Teflon powders, but in order to avoid legal action on the basis of copyright and trademark infringements, the name Teflon was replaced with anything the additive manufacturers could think of. However, the active ingredient still remained Teflon, but worse, some additive manufacturers elected to obtain their Teflon from other sources. In practice, this means that much of the Teflon in aftermarket additives are of substandard quality, apart from the fact that the particles may be several times as big as that made by Du Pont. The Slickest Product on Earth! So how is Teflon supposed to work anyway? One misconception is perpetuated by the claim that Teflon “bonds” to the friction surfaces inside engines, thus reducing wear by up to 80%. This is simply not true, since Teflon needs to be heated to 8000F before it will bond to metal. No engine ever gets that hot, which gives the lie to the claim of “friction-reducing layers”. Another, albeit less common misconception involves the “fact” that the colloidal Teflon particles act as “miniature” roller bearings between friction surfaces, thus eliminating direct contact between metal surfaces. The fact is however, that the clearances between friction surfaces in modern engines are too small to allow this to happen. What does happen though is that it is the zinc molecules in motor oil that act as “roller bearings” between surfaces. Regardless of how smooth or well polished a surface may appear to the naked eye, the fact is that all surfaces are marked by microscopic “valleys” and “peaks”, and by sliding across one another, the zinc molecules form a barrier between the peaks, while the valleys act as little reservoirs to hold a steady supply of oil. The shear strength of Teflon is simply not up to the task of forming a similar barrier, which only starts to break down when the relative movement between friction surfaces start to exceed the thickness of the protective layer of zinc molecules. If there were no wear agents in an engine, such as metal, carbon, and sulphuric acid, the zinc component of oil would protect that engine forever; but the fact is that at some point, the peaks on friction surfaces come into direct contact with one another, which is when no friction reducing agent can offer further protection, not even Teflon. Teflon and Oil Circulation Manufacturers of additives that contain Teflon powder claim that since the diameter of colloidal Teflon particles is less than one micron (one millionth of a meter), or one 25 4000th of an inch, there is no possibility of the powder clogging oil filters or oil passages. This may be true of a new filter on first use, but bear in mind that as a filter collects particulate matter, its capacity to collect ever-smaller particles increase, since the filter medium is progressively more clogged as time passes. So What Happens To The Teflon In The Oil? This is a very good question. For one thing, it may pass freely through the filter at first, but as time passes and the filter’s ability to catch ever-smaller particles increases, it is certain that more and more Teflon articles will be held inside the filter. In practice, this means that eventually, ALL of the Teflon particles will be filtered out, thus decreasing oil flow since the filter media will now be close to the point where no oil can pass through it . However, this also means that since the filter is clogged, ALL of the oil will bypass the filter via the pressure relieve valve, which means that the engine is deprived of the benefit of an oil filter. This writer operates a repair shop, and has personal experience of this, and other blockages of oil passages by the Teflon component of aftermarket oil additives, which begs this question- “Why do you want to put something in your engine that is almost certain to destroy it by clogging the oil filter?” Snake Oil? In the interest of fairness though, not all aftermarket oil additives contain Teflon, but then again, the active ingredients are never listed on the labels. For all you know, you may be buying decanted, regular oil at several times the price for a similar amount, or worse, you may be buying a product that contains “normal” additives in proportions that may not be compatible with any regular oil. The net result of this is the possible formation of sludge, gums, and varnishes that can increase mechanical wear, if they do not block oil galleries first. Of course, these problems take some time to develop, but since you cannot see inside your engine, you may not be aware of the problem, but by adding an additive in which the proportions of additives are unknown, the problem could reach crisis proportions very rapidly. The fact is that you simply do not know what you are buying, so why take the risk? The Federal Trade Commission has fought may battles against the producers of aftermarket oil additives, and although it has lost some, it has won most, so before you believe another claim that states you can reduce engine wear by up to 80%, ask yourself why so many manufacturers of these products end up in serious trouble with the law. If you want to learn more about the details of these legal battles, you can find more information on the Federal Trade Commission search page for any oil additive.