Gas stations in the US and many other nations are required to supply customers with consistent and clean gasoline. This means that no matter where the tank gets filled up, gas quality or the brand of gas will not noticeably affect how the vehicle performs. Some brands offer fuels with added cleaners and other additives. These can offer some benefits, but the fact remains that cheap gas that doesn't contain these additives is not dangerous or problematic.
As automotive technology has advanced in recent decades, automakers around the world agreed that government requirements for fuel additives were not adequate since they have not changed to meet the performance demands of modern vehicles. If a fuel company can prove that their gas has additives and detergents that keep residue from building up on valves or in the combustion chamber, then they are qualified to call themselves a "top-tier" gasoline supplier. Top-tier fuel is formulated to keep engines running efficiently and reliably. Automakers claim that these requirements makes gas better for modern cars.
Prominent top-tier gasoline suppliers
- Kwik Trip
The advantages of top tier gas
While the detergents and cleaning agents found in top-tier fuels may have some added benefit, there will be no noticeable difference in performance from behind the wheel. Top-tier gas companies have simply committed themselves to selling fuel specifically formulated for the needs of modern cars, but other regulations require that all fuel companies meet certain standards that prevent them from selling subpar gas.
While some gas stations offer slightly higher quality gas, any fuel from a legitimate gas station in the US will be fine to put into your tank. There's no issue with mixing fuel from different companies, either.