Many of us will remember the days when you were at a petrol stationthrow in $5 of 87 octane and go for miles without worry. Those days are over and have been for a while, as Energy.gov’s recent Fact of the Week Research has shown that since 2018, automakers have been recommending premium fuel for most light-duty vehicles.
More than half of all light-duty vehicles come with a recommendation for premium fuel. This is a significant increase from the 6.5 percent of vehicles that required premium fuel in 1985. Part of that growth is due to automakers’ move to smaller turbocharged engines and higher compression, which require higher octane ratings.
While it is still possible to buy a car that doesn’t do it require high test quality fuelThe number of available models has declined fairly consistently over the past two decades. Vehicles requiring midgrade gasoline were only removed from the figures in 2011, but the category has since represented a small number of available models.
Octane ratings measure the ability of a fuel to stop “pinging” or “knocking.” While there are outliers, such as racing fuel, most gas stations in the United States offer three octane ratings, ranging from 87 for regular fuel to 93-94 octane for premium. the higher the octane numberthe more resistant the fuel is to knocking at higher compression levels, allowing automakers to extract more power from smaller, more fuel-efficient turbocharged engines.
While it is always a good idea to follow your vehicle manufacturer’s recommendations, there may be times when premium fuel is not available. The advanced engine control systems in newer vehicles can often adapt to lower octane fuels, but they can suffer from a fuel economy or a power hit on the road. At the same time, using premium fuel in a vehicle that is not designed to take advantage of it may provide little to no benefit and costs a lot more in the process.