In this episode of Inside the Brands, CRP Automotive’s Mark Malone addresses a tricky question: “How do you know if an oil that is marketed as ‘synthetic’ is truly synthetic?”

Not so long ago, synthetic oil was a new concept in the marketplace. Now it seems like virtually all oils spec’d for new and late model cars are either a “full synthetic” or a “synthetic blend”. Synthetic oil — that is, oil which consists of man-made compounds — has really taken over the market, especially for newer vehicles.

But how does one know if what’s in the bottle is truly synthetic?

The answer is not as straightforward as you’d think. Because while the 120 viscosity index has traditionally marked the line between API Group II and Group III oils, there are NO short-term tests to validate the base oil group that a motor oil contains. API Group III base oil — which while derived from natural crude oil — is refined to a point where it’s considered a synthesized hydrocarbon.

Since there is no short-term test, this means that it is literally impossible for a user to tell if an oil that’s labeled “synthetic” is indeed synthetic. The only one who truly knows is the oil manufacturer.

Original Equipment manufacturers — like Fuchs Lubricants, the manufacturer of Pentosin fluids — are primarily focused on first fill oils. They invest heavily in their R & D departments and have limited marketing budgets. However, other brands which have no OEM first fills are focused on marketing and not R & D or approvals. These marketing companies can, at times, muddy the waters on what are true synthetics and what are blends.

So what to do? First, understand that in North America, “full synthetic” is really no more than a marketing term. And while Group III hydrocarbon oils are considered “full” synthetic, in some cases they can contain less synthetic chemicals than they do petroleum base oil.

What really matters on the label are the OEM approvals, specs, and certifications that an oil brand has. If an oil is certified and approved for your vehicle application, that’s really all you need to know.

The question also underscores the importance of getting your oil from a manufacturer you can trust. Rest assured that the Pentosin brand of oils and technical fluids is owned by Fuchs Lubricants — the world’s largest independent lubricant manufacturer.