Which engine oil type is recommended for use in the HMMWV?

The recommended engine oil type for the HMMWV is OE/HDO 15W-40 due to its specific properties that align with the operational requirements of the vehicle. This oil provides a good balance between viscosity and temperature performance, making it suitable for a wide range of environmental conditions that the HMMWV may encounter. The multi-viscosity nature of 15W-40 ensures adequate lubrication during both cold starts and high-temperature operations, preserving the integrity of the engine components.

Additionally, this oil type meets the military standards designed for use in tactical vehicles, which demand high-performance lubricants for durability and reliability in diverse operational environments. Using OE/HDO 15W-40 contributes to optimal engine performance, fuel efficiency, and longevity of the HMMWV, encapsulating the specific needs of the vehicle in service. Other oil types listed may not meet these stringent requirements or provide the necessary performance characteristics suitable for HMMWV operations.