U.S. drivers wasted more than $2.1 billion dollars in the last year by filling regular vehicles with pricier premium-grade gasoline, despite there being no tangible benefit to doing so.
The AAA researchers who carried out the study came to this conclusion after testing 87-octane (regular) and 93-octane (premium) gasoline in vehicles, then evaluating them for their performance, fuel economy and emissions.
The test results found no significant increases in any tested category, which indicates that there is no advantage to using premium gasoline in a vehicle that only requires regular-grade fuel.
AAA found that 16.5 million U.S. drivers unnecessarily used premium-grade gasoline in their vehicle at least once over the past year. In the same timeframe, they discovered that U.S. drivers unnecessarily used premium gasoline in their vehicle more than 270 million times.
“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. He urged drivers to follow the owner’s manual recommendations for their vehicle’s fuel in the future.
More Must-Reads from TIME
- Donald Trump Is TIME's 2024 Person of the Year
- Why We Chose Trump as Person of the Year
- Is Intermittent Fasting Good or Bad for You?
- The 100 Must-Read Books of 2024
- The 20 Best Christmas TV Episodes
- Column: If Optimism Feels Ridiculous Now, Try Hope
- The Future of Climate Action Is Trade Policy
- Merle Bombardieri Is Helping People Make the Baby Decision
Write to Kate Samuelson at kate.samuelson@time.com