Car News

Synthetic Oil vs. Conventional: What's the Difference?

RELATED READING
RESEARCH BY MAKE
Toyota cars, trucks and SUVs Ford cars, trucks and SUVs Honda cars, trucks and SUVs Chevrolet cars, trucks and SUVs Jeep cars, trucks and SUVs Nissan cars, trucks and SUVs Lexus cars, trucks and SUVs Volkswagen cars, trucks and SUVs BMW cars, trucks and SUVs
Acura cars, trucks and SUVs Alfa Romeo cars, trucks and SUVs AMC cars, trucks and SUVs Aston Martin cars, trucks and SUVs Audi cars, trucks and SUVs Bentley cars, trucks and SUVs BMW cars, trucks and SUVs Bugatti cars, trucks and SUVs Buick cars, trucks and SUVs Cadillac cars, trucks and SUVs Chevrolet cars, trucks and SUVs Chrysler cars, trucks and SUVs Daewoo cars, trucks and SUVs Datsun cars, trucks and SUVs DeLorean cars, trucks and SUVs Dodge cars, trucks and SUVs Eagle cars, trucks and SUVs Ferrari cars, trucks and SUVs FIAT cars, trucks and SUVs Fisker cars, trucks and SUVs Ford cars, trucks and SUVs Freightliner cars, trucks and SUVs Genesis cars, trucks and SUVs Geo cars, trucks and SUVs GMC cars, trucks and SUVs Honda cars, trucks and SUVs HUMMER cars, trucks and SUVs Hyundai cars, trucks and SUVs INFINITI cars, trucks and SUVs Isuzu cars, trucks and SUVs Jaguar cars, trucks and SUVs Jeep cars, trucks and SUVs Kia cars, trucks and SUVs Lamborghini cars, trucks and SUVs Land Rover cars, trucks and SUVs Lexus cars, trucks and SUVs Lincoln cars, trucks and SUVs Lotus cars, trucks and SUVs Maserati cars, trucks and SUVs Maybach cars, trucks and SUVs Mazda cars, trucks and SUVs McLaren cars, trucks and SUVs Mercedes-Benz cars, trucks and SUVs Mercury cars, trucks and SUVs MINI cars, trucks and SUVs Mitsubishi cars, trucks and SUVs Nissan cars, trucks and SUVs Oldsmobile cars, trucks and SUVs Plymouth cars, trucks and SUVs Pontiac cars, trucks and SUVs Porsche cars, trucks and SUVs RAM cars, trucks and SUVs Rolls-Royce cars, trucks and SUVs Saab cars, trucks and SUVs Saturn cars, trucks and SUVs Scion cars, trucks and SUVs smart cars, trucks and SUVs SRT cars, trucks and SUVs Subaru cars, trucks and SUVs Suzuki cars, trucks and SUVs Tesla cars, trucks and SUVs Toyota cars, trucks and SUVs Volkswagen cars, trucks and SUVs Volvo cars, trucks and SUVs Yugo cars, trucks and SUVs
RESEARCH BY STYLE
AWD/4WD
Commercial
Convertible
Coupe
Hatchback
Hybrid/Electric
Luxury
Sedan
SUV/Crossover
Truck
Van/Minivan
Wagon

author photo by Joe Tralongo June 2015

Synthetic motor oil has been around for a while now, but with recent advances in engine technology, more manufacturers are recommending either synthetic or synthetic blends to prolong engine life and improve fuel economy.

What Is Synthetic Oil?

Synthetic lubricants are derived from a number of sources, including completely synthetic compounds, petroleum-based products or other organic oils. Synthetic oil differs from conventional oil because of unique polymers added to the base formulation. This process creates a lubricant that's better able to withstand high temperature without losing its viscosity, or in layman's terms, its thickness. There are also so-called synthetic blends that contain no more than a 30 percent conventional oil base. These oils have many of the protective properties of pure synthetic oil but usually cost less.

Which Is Better?

Engine oil is there to protect moving internal parts from damage caused by friction and heat. As such, synthetics are superior to conventional oil because they deliver better lubrication during extreme cold weather and retain their viscosity even after prolonged use. Synthetic oil can also reduce sludge buildup in the oil passages, prolong engine life and improve fuel economy, so while synthetic oil does cost more than conventional oil, it lasts longer, meaning fewer oil changes. In fact, while it is recommended that conventional oil be changed between 5,000- to 7,500-mile intervals, using synthetic oil can extend those numbers to 10,000 miles or more.

We know a quick search of the Internet will expose numerous articles preaching that owners can go 10,000, 15,000 or even 20,000 miles between changes using conventional oil. We don't recommend pushing your oil-change interval this far, primarily because while oil formulations have improved over the years, oil-filter technology has not. A dirty or clogged oil filter can allow dirt and grime into the oil, and in the long run, can be as damaging to an engine's life-span as oil that has lost its viscosity. For this reason, we strongly recommend always adhering to the manufacturer's recommended schedule for oil changes.

Do I Have to Use Synthetic Oil in My New Car?

All cars, even older models, will do better with synthetic oil, but many newer cars actually recommend synthetic oil as part of the car's regular maintenance. Take, for example, Mazda's new SKYACTIV engine technology. To achieve maximum fuel economy and power, Mazda's new-generation engines employ extremely tight tolerance and have high engine-compression ratios. The superiority of synthetic oil is a big part of keeping Mazda's engines at their peak performance, which is why Mazda specifies 0W-20 engine oil. Note that while Mazda does not say synthetic oil must be used, the engine oil weight of 0W-20, specifically Castrol 0W-20, is only available in synthetic or synthetic-blend formulations. Mazda told Autotrader that customers can use conventional oil with the SKYACTIV engines and it won't void their warranty, but if you care about protecting your investment, we strongly advise that you follow the manufacturer's recommendations.

On a larger scale, all General Motors vehicles produced after 2011 are also required to use synthetic oil, and it has to be an oil that meets GM's own dexos specifications. The new dexos specification was invented by GM, and it basically sets standards that only a synthetic or synthetic-blend oil can meet. You don't have to use GM's own ACDelco brand, but you must use a blend that meets the requirements set by GM. There was a bit of controversy when this new policy first debuted in 2012 because customers were led to believe that, if they didn't use GM's ACDelco brand dexos oil, their warranty could be void. GM has since clarified its stance, stating that as long as the brand of oil bears the dexos label, it meets the vehicle's warranty requirements.

The long and short of the synthetic motor oil debate is that, for most vehicles, whether they are V8-powered SUVs or turbocharged 4-cylinder sports cars, the use of synthetic oil is one of the least expensive steps owners can take to prolong their car's life.

This image is a stock photo and is not an exact representation of any vehicle offered for sale. Advertised vehicles of this model may have styling, trim levels, colors and optional equipment that differ from the stock photo.
Synthetic Oil vs. Conventional: What's the Difference? - Autotrader