Many people still have this idea that premium gas is better all-around for their car. They swear that they get significantly better mileage and that their car runs better. It’s part of human psychology, really. We want to believe we make good decisions, so we justify things after the fact or we gravitate towards things that confirm that whatever decision we made was the right one. It's just human nature that people want to believe they are smart and that they make rational decisions.
That’s why it’s difficult to hear when new information comes out that implies a decision we made wasn’t as smart as we assumed it to be. AAA has been examining the buying habits of American consumers when it comes to gasoline. And the results of a new study recently released seem to indicate that there are lots of people who are wasting money on buying premium gas that’s not giving them the kind of benefits they think it is.
70% of cars out there don't need premium gas
The biggest factor in whether you’ll get any extra benefit with premium gas is whether your car’s engine specifically is designed to run on it. But 70% of the cars out there aren’t designed to need premium gas – they only need regular gas. Only 16% of cars out there today require premium gas (the remaining 14% either need midgrade or use an alternative energy source).
But so many drivers out there are convinced that there’s just something better about gasoline labeled ‘premium’. They assume it’s higher quality or has more detergents or is purer. None of that is, by and large, true. What *is* true about premium gas is that it is higher octane. But that has nothing substantially to do with its quality. If your vehicle’s engine isn’t engineered to require premium gas to run at its best, you do not need premium gasoline. You only need regular gasoline. You don't need to spend that extra money.
How do you know what your vehicle really needs? The owner’s manual will tell you pretty clearly. Yet 16.5 million drivers regularly ignore these recommendations and waste their money on more expensive premium gas that they don’t need.
Putting premium vs regular gasolines to the test
AAA put all this to the test by taking vehicles in Southern California that all require just regular gasoline. They tested V6, V8 and I4 engines to get a cross-section of effect. They put the cars on a dynamometer (a standardized testing machine for automobiles) and operated them through various controlled driving cycles while examining gas mileage, horsepower, performance and emissions. All while comparing how the cars did on both regular gas and premium gas.
The result? No real difference in gas mileage between regular gas and premium gas. No difference in horsepower, either. Or emissions. No significant difference in how those vehicles did, at all.
So, unless your vehicle specifically calls for using premium or mid-grade gas (and if it does, you better follow those recommendations), then just save your money and use regular gas.