Are there really some cheap brands of gasoline that won’t perform as well as name-brand gas station gasoline? I’ve heard stories over the years of never buying gas from a gas station because it’s watery, or only buying this brand because it gives better gas mileage. Do any of these stories have a real basis?
The real fact is that 99% of all gasoline in the United States is of good quality. Many gasolines, regardless of brand, probably come from the same source and are refined at the same refinery. They are probably even shipped in the same pipeline and stored at the same storage terminal.
So what is the difference, if any, between brands of gasoline? These are additives that are added to gasoline. All gasoline in the United States contains additives to meet federal EPA standards, even cheap gasoline from gas stations. There is a difference between brand name and generic additives, but how much of a difference is there and does it really make a difference to your car’s performance?
Additives are added to gasoline when the gasoline is loaded onto tanker trucks just before it is delivered to a service station. Until then, all gasoline is the same. The amount of additives added varies, but for some brands it is only a quarter of the additives for 8,000 gallons of gasoline.
What will have the greatest impact on the quality of the gasoline is the quality of the tank at the gas station, the tanker truck, and the consistency of the suppliers in the chain to maintain the quality at a certain standard. That affects gasoline more than additives. Consumer Reports tried to test the differences between brands of gasoline, but gave up when it realized the differences were nothing more than differences caused by factors like temperature and humidity.
There will be differences in gasoline in different parts of the country. Winter gasoline volatility in Connecticut will be very different than gasoline in Arizona. Also states and regions have different regulations and standards on the quality of gasoline. Some areas may require gasoline to reduce emissions. In reality, you may be running into a bad batch of gas, but it’s down to the individual gas station rather than the brand.
The best thing to do is find a service station that is convenient for you, is reasonably priced, and has a consistent supplier. There’s really no reason to change gas stations if you’ve found one that works for you. But only use the grade of gasoline that your car manual specifies, as that will save you money and headaches down the road.