Some of us pay a lot of attention to what we put in our gas tank. For others, it’s all about which option is cheapest.

But KHOU 11 viewer Lawrence Newman wrote in, asking us to verify whether name-brand gas is better than H-E-B, Kroger and Buc-ee's.

AAA completed a study just last year looking into which kinds of gas are better for your car.

“Long-term use of Top Tier gasoline with an enhanced additive package led to a reduction in fuel economy issues, drivability issues and lower emissions, which is a good thing,” said Sarah Schimmer, AAA Texas spokeswoman.

CHECK IT OUT: Full list of Top Tier brands

Top Tier doesn't just mean top brands, such as Chevron, Texaco or Shell. It's a specific distinction given to a lot of companies you might not think of as name brands.

To understand how this all works, you have to go back to the beginning of the process. Oil goes into the refineries where it's turned into gas. That goes into a terminal, from which all companies get their gas. It's what they do afterward -- mixing in additives and detergents -- that sets their product apart.

“Even an unbranded fuel marketer may add certain detergents or additives or whatever it may be as well,” said Paul Hardin, Texas Food & Fuel Association president. “It’s not the same proprietary additives as a Shell or Exxon Mobil may have.”

“Shell gasoline, being a Top Tier brand, contains a formulation of additive packages that are exclusively designed for our gasoline,” Shell fuels scientist Sarina Arnold said. “In addition to cleanliness, we also look at other engine attributes or attributes that the fuel can provide to the engine in terms of benefits.”

CLICK AND SEE: Top Tier brand or not?

When it comes to retailers such as Buc-ee's, Kroger, and H-E-B, if they buy Top Tier inventory, they can display a logoed sticker at each station.

“That lets the consumer know that is Top Tier-labeled quality gasoline,” Schimmer said.

No one from H-E-B, Kroger or Buc-ee’s could confirm to KHOU 11 News what kind of fuel they use, though a representative from H-E-B made the following statement: "H-E-B stands behind all of our products, inclusive of gas."

Reporter Brandi Smith drove to individual stations to check, but could find no sign of the Top Tier logo.

As a result, KHOU 11 News can verify that fuel from most brand-name gas companies is better than that you will find at Kroger, Buc-ee’s and H-E-B.

For a full list of Top Tier companies, tap/click here.

VERIFY: Sources

Sarah Schimmer, spokeswoman for AAA Texas

Paul Hardin, president of the Texas Food & Fuel Assn.

Sarina Arnold, Shell Fuels Scientist