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AAA Reports Not All Gasoline Created Equal

Most of us buy our gasoline the same way we buy sugar: by price, not brand. There was a lot more brand loyalty back when gas was $0.30 a gallon compared to today. Oil companies such as Shell and Texaco actually hyped their level of customer service and fuel quality, claiming cleaner engines, better mileage, friendlier service and so forth. “You can trust your car to the man who wears the star!” was the Texaco jingle. Today, it’s all about price per gallon.

As gas prices rose into triple digits, car owners focused more and more on pricing posted on gas station signage and less on the benefits of any particular brand. Gas is gas, right? Not really, according to results of testing by the nonprofit motoring organization AAA. Its findings show that performance and engine life can be enhanced by the fuel we buy.

Price and Convenience

AAA found that more than 60 percent of U.S. drivers believe there is a difference in gasoline quality from one brand to the next, but:

  • Three quarters of drivers buy gas according to location (75 percent) or price (73 percent).
  • Roughly 30 percent of drivers choose a gas station based on a rewards program.
  • Nearly half of all drivers don’t regularly buy gas containing an enhanced detergent additive.
  • Only 12 percent of drivers choose a gas station offering fuel with an enhanced detergent package.

When choosing between fuel quality or price and convenience, drivers will nearly always opt for price and convenience.

What’s the Difference?

There’s a lot of chaos in an engine as it runs. Fuel doesn’t simply pass through it; it ignites. Even burning a piece of paper leaves some ash and residue behind. Likewise, igniting fuel in your engine leaves behind a carbon residue. A buildup of this carbon residue will drag down fuel efficiency (fewer miles per gallon), increase emissions and make your engine work harder, increasing wear and tear.

The proper amount of detergent additives in fuel can prevent carbon residue buildup in today’s engines, but they add to the per-gallon cost — about three cents, according to AAA.

EPA Standards

In 1995, the government, through the Environmental Protection Agency (EPA), mandated oil companies to add a certain amount of detergents to each gallon of gas. However, as car engines have evolved and become ever more complex, several carmakers believe EPA standards haven’t kept pace.

Carmaker Solutions

Eight carmakers — General Motors, Fiat Chrysler Automobiles, BMW, Honda, Volkswagen, Mercedes-Benz, Toyota and Audi — that are convinced the EPA detergent additive standards fall short have come together in support of a higher standard for detergent fuel. Known as TOP TIER, it is currently the highest cleanliness standard for fuel performance.


TOP TIER is a class of fuel containing greater deposit control capabilities agreed upon by the participating carmakers. To meet TOP TIER standards, a gasoline brand must meet this higher standard of engine cleaning through deposit-control additives, cannot include harmful metallic additives and must be available across all octane levels.

According to AAA, roughly one out of three gas stations offer the TOP TIER standard for fuel.

AAA Findings

Choosing a market in southern Texas with fuel representative of gas sold across the United States, AAA secured the expertise of an independent company to compare deposit buildup in cars using TOP TIER fuel versus cars using non-TOP TIER gas.

After just 4,000 miles of simulated driving, the amount of carbon-deposit buildup in cars not using TOP TIER fuel was 19 times greater than in those using it.

What it means to you: A cleaner engine means less wear and tear, better performance and fewer emissions. Most gas stations pumping TOP TIER gas display the TOP TIER logo. Find out more at TOP TIER Gas.

Russ Heaps
Russ Heaps
Russ Heaps is an author specializing in automotive, financial and travel news. For nearly 35 years he has covered the automotive industry for newspapers, magazines and internet websites. His resume includes The Palm Beach Post, Miami Herald, The Washington Times and numerous other daily newspapers through syndication. He edited Auto World magazine, and helped create and edit NOPI Street... Read More about Russ Heaps

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  1. This report “fell short” by not citing the gas stations that carry TOP TIER gas, before sending us to an other site for additional info!!!

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