Many drivers spend more on gas than they need to because they're filling up with premium gasoline for which their vehicles are not designed.

NBC News reports that a study by AAA found that for 84% of cars on the road, premium gas does little to improve the vehicle's performance, mileage or engine protection.

"Drivers are wasting about $2.3 billion every year using premium fuel when the regular fuel would be just fine for their vehicles," AAA spokesman Doug Shupe said.

An average driver can save $300 this year by switching from premium to regular, according to NBC News.

Gas pump
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