The High Cost Of High Fuel Economy

Cars today are getting better fuel economy than ever. Even the big, hulking trucks and SUVs that Americans crave now get EPA mileage ratings that fall into the “not awful” category. But a funny thing has happened on the way to better fuel economy. Most manufacturers now use smaller, turbocharged engines in place of the legendary V-8s that powered the golden age of American cars. They recommend using premium gasoline in those new, more highly stressed engines.

fuel economy and premium fuel

The folks at Automotive News have noticed a disturbing thing happening in the marketplace. The price of regular gas may have plummeted, but the price of premium has not. Traditionally, the good stuff cost about 7% more than regular. In a story dated today, Automotive News says, “At a Shell station in Tucson, Ariz., regular gasoline cost $1.17 a gallon earlier this month, according to, while premium was $1.75. That’s nearly 50% more. In Chicago, a Pilot station had regular for $1.95 and premium for $3.09, 58% more. And an Exxon station in Newport News, Va., offered regular for $1.59 and premium for $2.89 — 82% more.”

Those may be extreme examples, but if you look around your neighborhood, you will probably find that people who are buying premium gas are getting hosed at the pump. On a percentage basis, the gap between the regular and premium has tripled since 2013 and more than doubled just since August.Which raises the question, is using premium necessary to avoid damage to the engine?

Tiago Castro, senior manager of product planning for Nissan North America says, “We recommend premium fuel, but customers can feel free to use regular. At some point, they may not see the value in premium. We make it clear it’s recommended, not required.” Nissan recommends premium for its Maxima and Juke models.

“If it says ‘premium recommended,’ then you don’t have to — why spend the extra money?” said Carroll Lachnit, a consumer advice editor at “But you’re not going to save that much money, so if you’ve spent the money on a sports car or a luxury car, don’t cheap out now.”

Years ago, before electronic fuel injection systems replaced carburetors, using low cost gas in high compression engines could indeed lead to engine damage. But today’s sophisticated cars have one or more knock sensors built in. Using data provided by those sensors, the car’s computer can adjust timing and fuel flow to adapt the engine to whatever grade of gasoline is being used. Regular may not give drivers all the performance their engine is capable of, but it probably won’t do any damage, either.

Ford Motor Co. recommends premium for the 2016 Escape with a twin scroll EcoBoost engine, the Flex with EcoBoost and most Mustang variants. But spokesman Paul Seredynski said none of the company’s vehicles requires premium for everyday driving. “EcoBoost engines don’t require premium fuel,” Seredynski said. “Ford recommends that you don’t go below 87, but all modern engines simply adapt to whatever fuel you put in.”

Don’t tell that to Daimler, the people who make the Smart Car, though. It says the ForTwo gets 3 mpg better fuel economy using premium than regular. The 2016 ForTwo’s owner’s manual cautions that using less than 91 octane fuel “can lead to engine failure.” Ahmad Bachan, the Smart brand manager at Loeber Motors in Lincolnwood, Ill., said customers don’t seem to mind using premium and that the risks created by trying to save a few dollars are too great. “You still can use regular,” Bachan said, “but it doesn’t give you the same quality, it doesn’t give you the same mileage, and in the long term it will ruin the engine.”

Higher fuel economy is not much of a benefit if you are paying 50% more for your gas. If you have any questions, you should consult your dealer and follow the manufacturer’s advice. If the people who made your car require you to use premium fuel, then that is what you should do.



Steve Hanley

Closely following the transition from internal combustion to electricity. Whether it's cars, trucks, ships, or airplanes, sustainability is the key. Please follow me on Google + and Twitter.