Gas Type by Car: Regular, Premium, Diesel or E85 / Buick / EnvisionBuick Envision Gas type by year YearGas type2026Regular2025Regular2024Regular2023Regular2022Regular2021Regular2020Depends on engine: premium or regular2019Depends on engine: premium or regular2018Depends on engine: premium or regular2017Depends on engine: premium or regular2016Premium Source: U.S. EPA / DOE fuel economy data (fueleconomy.gov).