Originally Posted by AAA
After using industry-standard test protocols designed to evaluate vehicle performance, fuel economy and emissions, AAA found no benefit to using premium gasoline in a vehicle that only requires regular-grade fuel.
“Drivers see the ‘premium’ name at the pump and may assume the fuel is better for their vehicle,” said John Nielsen, AAA’s managing director of Automotive Engineering and Repair. “AAA cautions drivers that premium gasoline is higher octane, not higher quality, and urges drivers to follow the owner’s manual recommendations for their vehicle’s fuel.”
In partnership with the Automobile Club of Southern California’s Automotive Research Center, AAA tested 87-octane (regular) and 93-octane (premium) gasoline in vehicles equipped with a V-8, V-6 or I4 engine designed to operate on regular-grade fuel. To evaluate the effects of using a higher-octane fuel when it’s not required by the manufacturer, each vehicle was tested on a dynamometer, which is essentially a treadmill for cars that is designed to measure horsepower, fuel economy and tailpipe emissions when using both fuel types and variety of driving conditions. The laboratory testing found no significant increases in any tested category, indicating the practice of using premium gasoline when it’s not required for the vehicle offers no advantage.
“AAA’s tests reveal that there is no benefit to using premium gasoline in a vehicle that requires regular fuel,” said Megan McKernan, manager of the Automobile Club of Southern California’s Automotive Research Center. “Premium gasoline is specifically formulated to be compatible with specific types of engine designs and most vehicles cannot take advantage of the higher octane rating.”