The Great Motor Oil Debate: Synthetic or Conventional?

Which is right for you? This question is debated endlessly among shade-tree and expert mechanics. In the end, choosing the right motor oil can be a matter of preference as well as wisdom.

Conventional motor oil is ideal for a majority of vehicles when service intervals are followed per the manufacturer's recommended schedule. Higher-priced synthetics are normally factory-installed and recommended for higher-end performance cars, but may provide benefits to other cars as well.

So which should you use? The best advice is to honor your owner’s manual.

If you own a vehicle that requires synthetic, your answer is simple. You should always use synthetic since the manufacturer has designed its engine and services for synthetic's high standards.  And even if your car does not require it, if your driving habits include lots of short trips, you plan on keeping your vehicle for the long term (8+ years or so), or you frequently tow heavy loads, then it may be worthwhile to consider a switch to synthetic.

There is some evidence that synthetic oils provide cooler operation, decreased sludge/varnish build up, and improved fuel mileage. If conventional oil is approved for your vehicle but you decide to use synthetic instead, this choice should be made early in the car’s life (usually before the first 12k miles) so as to reap all the benefits of synthetic.

The down side of synthetic is the added cost of the oil itself (usually more than twice the price of conventional);  and once you have started using synthetic, you should not switch back to conventional or you will defeat the benefits you gained by switching to synthetic oil.

Choosing the right oil for your car can be daunting, but with these basic rules and your owner’s manual you can make an educated decision to help protect the life of your car.

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