Are you ever tempted to buy that premium gasoline at the pump? Some drivers think they are doing their car a favor. But new research by AAA shows that paying-up for premium may not be worth the extra money, unless the vehicle absolutely requires it.
While some vehicles are designed to run on premium octane gasoline, others simply recommend it. AAA set out to determine the effects of using premium gasoline in vehicles that recommend it and whether the benefits in fuel economy and horsepower are worth the higher price at the pump.
On average, this year in Michigan, there has been a 26 percent (64 cent) price gap between regular and premium octane fuel ($2.44 vs. $3.08). Michigan’s current state average price for a gallon of regular gas is $2.50 vs. $3.16 for premium, a 66 cent difference.
AAA tested a variety of vehicles that recommend, but do not require the use of premium (91 octane or higher) gasoline. A series of tests were conducted to determine whether the use of premium gasoline resulted in improved fuel economy and increased performance (horsepower).
Since drivers of these vehicles are unlikely to see any benefit from using premium gasoline during typical city or highway driving, a combination of laboratory and on-road tests were performed to simulate extreme driving scenarios such as towing, hauling cargo, and aggressive acceleration.
Test vehicles included a Ford Mustang GT, Jeep Renegade, Mazda MX-5 Miata, Cadillac Escalade ESV, Audi A-3, and Ford F150 XLT.
- Most vehicles showed a modest improvement in fuel economy and performance.
- Fuel economy for test vehicles averaged a 2.7 percent improvement. Individual vehicle test result averages ranged from a decrease of 1 percent (2016 Audi A3) to an improvement of 7.1 percent (2016 Cadillac Escalade).
- Horsepower for test vehicles averaged an increase of 1.4 percent. Individual vehicle test result averages ranged from a decrease of 0.3 percent (2016 Jeep Renegade) to an improvement of 3.2 percent (2017 Ford Mustang).
- Premium gasoline costs 20-25% more than regular.
The fuel economy improvements recorded during AAA testing do not offset the potential extra cost to purchase premium gasoline.
“Sometimes consumers think they are giving their vehicle a boost by buying a higher-grade gasoline than what is required,” AAA spokesperson Susan Hiltz said in a statement. “AAA already proved that there is no benefit to using premium gasoline in cars designed to run on regular. Now we can confidently say that unless the vehicle manufacturer requires it, or you drive in demanding conditions, motorists who buy premium are wasting money at the pump.”
Some motorists may consider the additional torque and horsepower to be worth the extra money. Individual drivers – particularly if their driving style can be described as “spirited” – may find an improvement in vehicle driving performance for off-the-line acceleration, highway passing, hill-climbing when loaded with luggage, or towing a trailer; and may determine that their personal driving benefits from the use of premium gasoline.
Drivers of vehicles that require premium gasoline should always use it. AAA urges drivers who use premium gasoline to shop around for the best price, as it could vary dramatically between gas stations in any given city.
For those vehicles that do not recommend or require premium gasoline, AAA suggests drivers opt for the lower priced, regular fuel.
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