Oil companies pump barrels of money into the effort to convince you their product is better than the competition's. Chevron's Techron-fortified fuel comes recommended by a fleet of gleeful autos; ConocoPhillips touts Proclean. Besides the price and fancy marketing, though, there's little difference between brandname gas and what you get at the momand-pop pump up the block.
"They're basically the same fuel," says Marcia Goggans, a chemist for the Motor Fuel Testing Laboratory in Maryland. In 2007, the lab compared discount and brand-name gasolines and came to the conclusion that the two were nearly identical.
That's not surprising, because by EPA mandate, every gallon of unleaded must be bolstered with detergents to keep emissions and engines clean. Then consider that most gas comes from the same sources. Suppliers share pipelines, and what you put in your tank at Texaco may have been refined by ExxonMobil, or vice versa.
To top it off, dealers can buy their fuel on the open market. That means the generic station could be selling you one of the big boys' house blends, and for less. So go on, fill up and save a buck. Grab a pack of gum while you're at it—if you don't mind blowing some of the money you just saved.
Shop for the least expensive fuel near you with the AAA Gas Price Finder. Visit AAA.com/gasprices for more information.
This article was first published in November 2009. Some facts may have aged gracelessly. Please call ahead to verify information