Toyota Avalon (XX50) 2019-2022 Owners Manual > Specifications: Fuel information
You must only use unleaded gasoline. Select octane rating 87 (Research Octane Number 91) or higher. Use of unleaded gasoline with an octane rating lower than 87 may result in engine knocking. Persistent knocking can lead to engine damage. At minimum, the gasoline you use should meet the specificati ...
