What are the best ways to extend motor oil service intervals?

There are many ways the average motorist can extend motor oil service intervals: From oil condition sensors to the relatively simple change to synthetic engine lubricant.

For many decades the motor industry considered 10,000 KM motor oil change intervals to be the best for proper lubrication. However with improved lubricants and developments in engineering 15,000Km is now the norm
for normal driving conditions.

Oil reminder lights can extend motor oil service intervals.

General Motors and a number of European vehicles have done away with recommended oil change intervals altogether in an effort to extend motor oil service intervals, and now use an "oil reminder" light to signal the driver when an oil change is needed. On some of these (Volkswagen, Audi, Mercedes Benz, BMW and Volvo), a scan tool or a special service tool is required to reset the oil service reminder light. On others, there is a manual procedure for resetting the oil reminder light.

DO NOT IGNORE THE LIGHT! When the light is on, it is time to change the oil.

The oil reminder systems estimate oil life based on engine running time, miles driven, ambient temperature, coolant temperature and other operating conditions. On some of these vehicles, the light may not come on until 18,000 Km or higher!

Typically the oil sensor monitors extend motor oil service intervals by measuring oil condition The latest technology for letting you know when your oil needs to be changed is electronic sensing. An oil monitoring technology originally developed for the military called is now available to consumers. The sensor replaces the dipstick and provides real time monitoring of the oil's true condition. This eliminates the guesswork and uncertainty that exists with recommended service intervals or oil reminder lights.

The monitors usually use a simple, patented conductivity test that applies low voltage with slow varying waveforms across two sensor arrays. The sensor measures changes in the electrochemical current flow caused by additive package depletion and impurities that accumulate over time in the oil. As more additives are depleted, most notably antioxidants and detergents, the oil's conductivity changes, which leads to a corresponding reduction in the sensor reading.

Using synthetic lubricants will also extend motor oil service intervals.

There are a number of quality synthetic motor oils available. The number of miles you can allow between oil changes will depend on the way you drive and the oxidation stability (useful oil life) of the motor oil. 


Oxidation stability is measured by the rigorous Thin Film Oxidation Uptake Test. Conventional motor oils typically last less than 300 minutes. Cracked synthetic motor oils typically last less than 500 minutes. However, quality, high-performance synthetic motor oil, such as that produced by Habot oil, has been shown to outlast the 1,300-minute test. These motor oils are recommended to extend motor oil service intervals to as much as 20,000Km under normal driving conditions. The motor oil has also been shown to improve fuel economy.

Be careful not to over extend motor oil service intervals?

Regardless of what type of oil you use (conventional, synthetic or synthetic blend), all motor oils eventually wear out and have to be changed (actually, it's the additives that wear out more so than the oil). As the miles add up, motor oil loses viscosity and gets dirty. The oil no longer has the same viscosity range it had when it was new, and it contains a lot of gunk (moisture and acids from combustion blowby, soot, dirt and particles of metal from normal wear). You can't really tell much about the condition of the oil by its appearance alone because most oil turns dark brown or black after a few thousand Km’s.

The oil filter will trap most of the solid contaminants when you extend motor oil service intervals, and the Positive Crankcase Ventilation (PCV) system will siphon off most of the moisture and blowby vapors, if the engine gets hot enough and runs long enough to boil the contaminants out of the oil. Even so, after several thousand miles of driving many of the essential additives in the oil that control viscosity, oxidation, wear and corrosion are badly depleted. At this point, the oil begins to break down and provides much less lubrication and protection than when it was new.

If you extend motor oil service intervals past the point of being useful, the oil may start to gel or form engine-damaging varnish and sludge deposits. Eventually this can cause your engine to fail! Oil sludge can damage engine bearings, piston rings, cylinder walls, valve guides and lifters.

Many fleets would like to extend motor oil service intervals. It saves time, saves money, and it’s better for the environment. But if you extend too much, it can damage the engines and lead to increased maintenance costs. We suggest you fully understand your OEM recommendations.