BMW 320d engines require specific oil formulations to maintain optimal performance and longevity. The type of oil recommended for a BMW 320d will depend on the model year and specific engine variant.
Generally, BMW recommends using a fully synthetic oil that meets the BMW Longlife-04 specification. These oils are designed to provide excellent protection against wear and tear, as well as maintain their viscosity over a wide range of temperatures. Some popular brands of oil that meet the BMW Longlife-04 specification include Castrol Edge, Mobil 1, and Pennzoil Platinum.