Synthetic or Conventional Oil?

What's It Worth?
Are synthetics worth the extra cost? Universally, the answer is yes, whether for a high-revving turbo motor or an older engine that gets little use. Using another vivid comparison, French champagne is also worth the extra expense over sparkling wine, but it comes down to matters of your taste and bank account. Note, too, that most auto manufacturers do not specify synthetics, so unless you're one of the few who need synthetic oil, rest assured that you're doing no harm with good old-fashioned crude as long as you follow the owner's manual recommendations on viscosity and grade.


On the other hand, synthetics are better on a number of levels. They keep the engine cleaner through improved sludge and varnish protection, reduce engine wear at high temperatures with more stable viscosity, protect the engine when it's running under severe conditions at high temperatures, provide better cold-temperature starts with faster oil flow at ignition and improve fuel efficiency.

Myths
As with any new technology, there are a number of myths and advertising claims that need to be explored. Back in the late 1990s, the National Advertising Division (NAD) of the Council of Better Business Bureaus ruled that "synthetic" could be defined as the product of an intended chemical reaction.


As a result of this battle of semantics, the NAD, the Society of Automotive Engineers and the American Petroleum Institute ended up with broad interpretations of "synthetic." What that means to the layperson is this: if you want full synthetic or semi-synthetic or whatever, read the label to make sure you're getting what you want and what you think you're paying for.


One urban myth surrounding synthetic oil is its compatibility with conventional oil. At one time, those who switched from conventional to synthetics had to stick with synthetics—there was no going back. Synthetics expanded the seals in the engine; then, when conventional motor oil was used, that engine sprang multiple leaks.