The 3 most important reasons why motor oil deteriorates.

It is common knowledge that, at some point, engine oil must be changed but many people don’t know why motor oil deteriorates, they believe it car oil merely becomes contaminated over time. They believe if you keep the oil clean, it will last forever. This is not true.

The fact is, all lubricants will fail at some point.
However, there are many ways to manage the condition of a motor oil thereby extending oil change intervals significantly.

There are three primary causes why motor oil deteriorates: degradation of the base oil, depletion of additives and contamination. Some of these conditions can be remediated, yet others cannot.

Base Oil Degradation is a critical factor in explaining why motor oil deteriorates.

Base oil degradation may be the most common reason why motor oil deteriorates. The most common type of base oil deterioration is probably oxidation. When engine oil oxidizes, the primary by-products are acids and insoluble materials, which can lead to damaging surface deposits and corrosive wear. To address this problem, most lubricants are formulated with antioxidants, but they don't last forever.

Contaminants also cause significant changes to the rate of oxidation, acting as catalysts for the reaction or, in the case of air, providing one of the reagents. Certain wear metals can dramatically increase the rate of this reaction, especially in the presence of water or combustion by-products.

The quality of the base oil used in the lubricant plays a role in the way motor oil deteriorates as well. Lower quality base oils tend to contain more inherently unstable constituents such as aromatics and other unsaturated hydrocarbons which more readily react with oxygen.

In addition to oxidation, base oils can fail due to thermal degradation, hydrolysis and various chemical reactions with contaminants. While mineral base oils and polyalphaolefins (PAO) have good hydrolytic stability, several types of synthetics are prone to reacting with water, which forms corrosive acids.

While it may be impractical to prevent base oil from failing, the factors influencing why motor oil deteriorates can be managed. Managing the oil's temperature, selecting a good-quality base oil, monitoring antioxidant concentration, and preventing or removing contamination goes a long way toward extending the lubricant's service life.

One means of extending engine oil service intervals is by using quality synthetic motor oil such as that produced by Habot Synthetic Lubricants. Today's engines are running hotter than ever. More horsepower, turbo chargers and aerodynamic styling have created extremely hot environments that receive less cooling from outside air. High heat leads to oil oxidation, deposits and thickening in conventional oils.

Because they are made from impure, irregular molecules, conventional motor oils are more susceptible to the effects of heat. The small, light molecules in conventional oil tend to evaporate as the oil is heated, leaving large, heavy molecules behind and leading to oil consumption and an increase in the oil's viscosity. If those large, heavy molecules are chemically unstable, they may also break-down and form deposits on component surfaces, further adding to the factors why motor oil deteriorates.

The excellent resistance of synthetic lubricants to thermal and oxidative breakdown allows them to be used for much longer drain intervals than conventional lubricants. Their uniform molecular structure allows synthetic engine oil to operate with less friction and better heat control than regular lubricants.

Why motor oil deteriorates because of additive depletion.

Like many oil additives, oxidation inhibitors are used up as they perform their intended function. Once these additives are consumed, the base oil begins to oxidize. Many factors contribute to oxidation including heat, contaminants and base oil quality. Oil temperature plays a large role in the rate of oxidation. For every 10-degree Celsius increase in oil temperature, the rate of oxidation doubles.

 Although many additives such as antioxidants enhance the properties of the base oil, other additives perform functions the base oil cannot. Antiwear, extreme pressure, detergents and dispersants are examples of such additives. Even if a lubricant's base oil is in good condition, the lubricant can no longer perform all of its duties when certain additives are depleted and, therefore, must be changed.

Additives are depleted by a number of different mechanisms. Water can react with certain additives (hydrolysis), and also can attract and remove others (water washing). Some additives are removed by particle contaminants (particle scrubbing), and others are simply used up when performing their intended functions.

Once again, these processes cannot always be eliminated, but they can be minimized. By using a well-chosen lubricant, maintaining proper oil temperature and controlling contamination, we can prevent any unnecessary additive loss, thereby reducing one of the influences on why motor oil deteriorates.

Contamination is a major factor in why motor oil deteriorates.

Many types of contaminants contribute to the degradation of lubricating oils, but that's not the worst of it. Of course, we all know that contaminants such as particles are responsible for the majority of mechanical wear in an engine. Because of this, we often change oil before it fails, simply to remove the contamination.

 However, changing oil to remove contamination will be only partially effective, at best. When the oil is changed in most engines, a significant portion of the old contaminated oil is left behind.

Considering the cost of engine repairs or replacement, ensuring your motor oil is up to the job of efficiently lubricating your engine is a worthwhile endeavor. If you examine the cost of changing the oil over the life of a vehicle, you might be shocked to see what you spend. The keys to achieving maximum life from lubricants are proper selection, temperature management, and good contamination control.

Many factors contribute to why motor oil deteriorates, but it is essentially the accumulation of contaminants in the oil and chemical changes in the oil itself that make the oil and chemical changes in the oil itself that make a motor oil unfit for further service. With time, it is inevitable that the oil will be contaminated by dirt or sludge, or succumb to the extreme pressures or temperatures found inside an engine. Habot Synthetic motor oils are formulated with the industry's most advanced synthetic base stocks and additive packages to combat the forces that deteriorate conventional oils.