engine oil dipstick

Synthetic motor oils typically perform better than conventional motor oils in protecting your vehicle. But why? Let’s explore the difference between synthetic and conventional oil.

Synthetic oil is refined like conventional oil, but is then also distilled, purified and broken down into its basic molecules. This removes more impurities from the crude oil and enables the oil to be tailored to the demands of modern engines. These customized molecules provide higher levels of protection and performance than conventional oils.

The properties that separate conventional oil from synthetics affect your engine in many important ways.

Improved lubrication. Most synthetic oils have added lubricants that increase the ability of the oil to keep engine parts slick, especially at high temperatures. This decreases wear over the long term, and may make your engine last longer.

Better stability. Synthetic oils’ viscosity at higher temperatures and over longer periods of time prevents engine wear in several ways. It allows the oil to “stick” to engine parts more readily, providing better wear protection, as well as doing a better job protecting your engine from dry starts.

Reduced breakdown. Synthetic oils are less apt to break down, meaning they don’t need to be changed as often as conventional oils. The more durable properties of synthetic oil also means that your engine is protected better through the whole service interval.

Fewer deposits. As conventional oils break down they can leave deposits on engine components, just like cooking oil would in a frying pan. Mechanics refer to these deposits as sludge or scaling. This is especially common in engines that run for long periods of time, or are driven hard. Synthetic oils are less apt to do this, though there are some conventional oils that have the ability to remove some of these deposits.

Synthetic oils cost more per litre than conventional oil, but there is not much of a cost difference if you allow your oil change cycles to last longer with synthetic. There is a debate on when you should change your oil, because the age old consensus has always been every 3 months or 3,000 miles, whichever comes first. But today’s synthetics are cleaner and meaner. Their composition is cleaner because it is derived in a laboratory (rather than nature) and it has been proven to have a lower volatility and therefore not vaporize out the exhaust as quickly.

Although the properties of synthetic oil are definitely superior, conventional oil will protect your vehicle’s engine just fine. The most important thing you can do to keep your car running smoothly is to follow your vehicle manufacturer’s recommended service intervals.