Gas Type by Car: Regular, Premium, Diesel or E85 / Audi / S6Audi S6 Gas type by year YearGas type2025Premium2024Premium2023Premium2022Premium2021Premium2020Premium2018Premium2017Premium2016Premium2015Premium2014Premium2013Premium2011Premium2010Premium2009Premium2008Premium2007Premium2003Premium2002Premium Source: U.S. EPA / DOE fuel economy data (fueleconomy.gov).