Oil Change: Facts vs Myths

Everyone from experts to amateurs tells us how important an oil change is for our car's safety and proper function. Myths have appeared about the oil change process and motor oil characteristics over the years that need to be corrected with facts. Here are some of the most common myths and the actual facts for your consideration.

Myth—Change Your Oil Every 3000 Miles ... Without Fail

Fact—Lighter and More Effective Oils Can Extend the Oil Change Period

In the days before oils formulated with detergents, emollients and other additives to keep engine parts cleaner, the 3000-mile threshold for oil changes was a useful benchmark. Modern oils are lighter while still retaining viscosity, and keep engines cleaner. It's not a problem now to go for up to 5000 or 6000 miles between oil changes. Certain vehicles that use oil as a lubricant for other parts of the drive train, such as the gear timing chain, need to have their oil changed more often.

Myth—Dark Oil is Unsafely Dirty

Fact—Soot in Oil Darkens It within a Few Days of Changing

The dark color of your oil is not a reliable guide to when it needs to be changed. A detailed oil analysis can tell you its composition and the percentage contamination it is carrying, but this is an unnecessary and expensive process. Just follow the recommended guide for oil changes from your car's maker and you will replace oil well before it is contaminated enough to contribute to engine damage.

Myth: Change Your Oil on the Same Schedule Wherever You Drive

Fact: Gasoline Composition Dictates Oil Changes

North American refiners produce gasoline that has a higher sulphur percentage than either Japanese or European gasoline. You will need to do more frequent oil changes when driving in the USA or Canada than in Europe or Asia.

Myth: You Need to Change Your Oil with the Seasons

Fact: Use 5W30 All Year, and 10W30 only in Very Warm Climates

5W30 oil is recommended for all-season use, even in very cold weather. You need only switch to 10W30 if you live where the temperature never dips below freezing.

Myth - Synthetic Oils Prevent Sludge

Fact - No Oil Prevents Sludge Formation

Sludge is a natural result of the combustion process in an engine. When motor oil is fresh, it can pick up the majority of the particles formed by burning of gasoline in the engine cylinders. As the oil becomes saturated, it can no longer hold particles in suspension and they drop out onto the engine parts, creating sludge. Some synthetic oils may be able to trap and hold contaminants for a longer time, but they do not prevent sludge formation.

Myth: Synthetic Oil Is Always Better

Fact: Synthetic Oil and Regular Oil Perform Equally Well

Synthetic oil is no better than natural oil for vehicles driven slowly in towns and cities, and at highway speeds, in a climate with moderate weather. It benefits only high-performance racing engines or vehicles that driven in very cold weather, below 0 degrees F. (-18 C.) for extended periods.