The American Automobile Association has an important message for Americans: we’re all wasting billions of dollars every year on premium gasoline for vehicles that don’t actually need it, and we should stop. While high-octane gasoline is available everywhere and might make us feel like we’re doing something good for our cars, we actually aren’t.

It’s not that putting higher-octane fuel into your car is going to hurt your car, but an additional survey by AAA shows that only 16% of drivers have cars with an engine type that can actually take advantage of high-octane gasoline and would benefit from it.

AAA performed lab tests on cars that only need regular gasoline, checking for changes in performance, fuel economy, and emissions from the car. They showed no difference with premium or midgrade fuel.

“Drivers see the ‘premium’ name at the pump and may assume the fuel is better for their vehicle,” the organization’s managing director of Automotive Engineering and Repair, John Nielson, said in a statement about the research. “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.”

There are times when you probably should buy higher-octane fuel even if your car isn’t designed for it: for example, if your region is experiencing fuel shortages and it’s the only thing still available, then it isn’t a waste of money. The rest of the time? Don’t bother: save the extra money for something else. The people behind this data would probably recommend a AAA membership.

Full Report [AAA]

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