The recommended fuel for optimal performance in a 2015 BMW 335i, equipped with the N55 engine, is premium unleaded gasoline. This type of fuel typically has an octane rating of 91 or higher. Using the specified grade ensures the engine operates as intended, providing the expected power and efficiency.
Employing the correct fuel grade is vital for the longevity and health of the engine. Higher octane fuels are designed to resist detonation, or “knocking,” which can cause significant engine damage over time. Historically, premium gasoline formulations have included additives that contribute to cleaner engine operation and reduced emissions.
