The downsizing trend means an assortment of mainstream vehicles are now equipped with turbocharged engines and a number of them recommend using premium fuel.
This is a pricey proposition as a recent study by AAA found the price gap between regular and premium gasoline has increased from 23 cents in 2009 to 50 cents today. That means filling up a 20 gallon tank would cost an additional $10 when using premium fuel.
Besides showing the growing price gap, the study found an interesting change. While the group's previous research determined there was no benefit to using premium gasoline in a vehicle designed to operate on regular fuel, the latest study found that "some vehicles – those that recommend, but do not require premium gasoline – may see increased fuel economy and performance under certain driving conditions when using the higher-octane gasoline."
As part of the study, AAA tested a number of vehicles that simply recommend premium gasoline. The results showed the vehicles posted an average fuel economy gain of 2.7 percent but those numbers varied from a 1 percent decrease in the Audi A3 to a 7.1 percent improvement in the Cadillac Escalade.
In terms of performance, horsepower ratings climbed an average of 1.4 percent on premium fuel. However, the Jeep Renegade actually lost power while the Ford Mustang gained 3.2 percent more.
Despite some positive results, AAA says the cost of premium fuel might outweigh the benefits in vehicles that don't require it. The group also noted the modest fuel economy gains would never offset the higher prices of premium gasoline.