If you routinely pump premium into your vehicle, you could be among the roughly 16.5 million Americans frittering away cash, according to a recent AAA analysis.
The research backed up what many automotive pros have suspected for years: “Premium” doesn’t mean better-quality gas, and most cars don’t actually need it.
So why did U.S. motorists, as AAA estimated, blow about $2.1 billion last year on unnecessary premium-grade petrol?
The Premium Gas Misconception
When you pull up at the pump and see three choices, it’s easy to assume each pricier option is superior to the previous one.
Maybe, like my dad used to tell my sibling and me, you opt for premium thinking it delivers better fuel efficiency, fewer emissions and overall improved longevity for your engine.
Sadly, that belief is mistaken, and it could cost you — and your unsuspecting family members — nearly $300 per year each.
Premium runs about 50 cents more per gallon than regular on average, CNN reports, and the typical American motorist uses 583 gallons yearly.
I usually trust my dad on basic car care — that’s practically his role. In this instance, though, he’s likely repeating an entrenched myth.
AAA’s recent tests compared vehicle behavior, mileage and emissions using both regular and premium fuels.
“AAA’s testing shows there’s no advantage to using premium gasoline in a vehicle that calls for regular fuel,” said Megan McKernan, manager of the Automobile Club of Southern California’s Automotive Research Center, which teamed with AAA on the study.
“Premium gasoline is formulated for specific engine types, and most cars can’t utilize the higher octane rating.”
What Is Premium Fuel — Do You Need It?
“Premium” simply denotes a higher octane level — not superior quality.
High-octane fuel can unlock more horsepower in performance-oriented cars, explained Justin Cupler, a former mechanic and automotive editor.
If you’re wondering what horsepower actually represents, Cupler kindly clarified: “Horsepower is essentially how quickly the car can accelerate.”
In short, more horsepower helps a car accelerate faster, aids towing and delivers stronger performance when climbing steep grades or in other demanding conditions.
Chances are your vehicle is among the many designed to run on regular fuel, so premium won’t boost its performance.
Putting premium in a standard car is like taking a supplement with 300% of your daily Vitamin C — you don’t get triple the benefit; the excess is simply passed through your system.
Driving a Performance or Luxury Car?
If you own a performance-oriented or luxury model engineered to make use of higher-octane fuel, you probably recognized that when you chose the vehicle.
Even many high-performance cars onlyrecommendpremium fuel, Cupler notes, and that recommendation is about preserving performance, not the vehicle’s basic safety.
Take the 2017 Mazda CX-9 as an example: its 2.5-liter turbocharged engine will run on regular (87 octane) but its electronic controls limit output to 227 horsepower.
Fill the tank with premium (93 octane) and the engine can achieve its full rating of 250 horsepower (translation: more speed).
Using regular in a premium-recommended car won’t immediately harm it or degrade performance permanently, because the vehicle’s computer detects potential knocking from lower-octane fuel and retards ignition timing. That ignition adjustment typically reduces the engine’s horsepower.
I could keep geeking out over automotive details, but I suspect you’re less interested in the minutiae and more curious about what to actually do with this knowledge.
Bottom line: Look at your owner’s manual.
“When it comes to gasoline, ‘premium’ does not mean ‘better’ if your vehicle does not require it,” said John Nielsen, AAA’s managing director of Automotive Engineering and Repair, in a recent release.
Check your manual for guidance:
- If it doesn’t recommend premium or show a performance boost with higher-octane fuel, spending extra on premium won’t benefit you.
- If it recommends premium, you’ll likely lose performance by using regular.
- If the manual states premium is “required,” you should pay the extra most of the time.
Occasional use of regular gas in a premium-required vehicle — say you’re short on cash — usually isn’t catastrophic, Cupler says. But continued use, especially in older engines, can cause knocking that might produce long-term damage.
If you hear that knocking sound, top up with premium as soon as possible, AAA automotive engineering lead Greg Brannon advised CNN.
New cars that list premium as required present another concern: although they’ll likely run on lower-octane gas, choosing the wrong fuel could risk voiding your warranty.
Only about 16% of U.S. drivers currently own a car that actually requires premium fuel, AAA reports.
Why Did My Dad Believe Premium Was Superior?
So why did my dad, who never owned a performance car, insist premium gasoline was better for the ancient Buick LeSabre I drove in high school?
Because “premium” used to really mean “better” gasoline.
Before detergents and other additives were mandated in 1997, these cleaning agents and emissions-reducing chemicals were primarily included only in premium grades. Back then, buying premium did help keep engines cleaner and lowered emissions.
That’s no longer the case.
Today, all available gasoline must include these additives by law. Octane rating is the only real distinction left between regular and premium.
Quality might differ by brand — not by grade — but every fuel sold at U.S. stations has to meet current standards.
So thanks, Dad — but I’ll take this chance to school you and save a few dollars at each fill-up.
Your Turn: Have you been overspending on premium gasoline?
Alex Reid is a staff writer at Savinly. He’s contributed to multiple outlets and likes to blend practical advice with a touch of humor whenever possible.
For related tips on saving money with basic car care, see car maintenance save money oil change.
