A frequent doubt among drivers is whether it is safe to mix gasolines from different brands or with different characteristics when there is still fuel in the tank. The question also extends to diesel and fuels discussions about possible impacts on engine performance, fuel consumption, and vehicle durability.
According to the ADAC, Europe's largest automobile club, there is no reason for concern when mixing compatible fuels, as long as both are suitable for the engine and comply with the specifications defined by the vehicle manufacturer. The idea that mixing 95 gasoline and 98 gasoline can cause engine damage is common, but specialists clarify that alternating use does not pose a problem for vehicles approved for different octane ratings.
The fuels sold in Europe follow strict standardized norms that establish very narrow quality margins. For this reason, there should be no substantial differences between fuels from well-known brands and those sold by smaller operators or so-called white-label brands, as long as they originate from official circuits and comply with legal requirements.
The most important exception that should never be ignored is never to refuel a gasoline vehicle with diesel, nor a diesel vehicle with gasoline. In those cases, mechanical damage can be significant and require specialized intervention.
