Mobil1Turbo Diesel Truck 5W-40 is a full synthetic heavy duty diesel motor oil that helps to extend engine life while providing long drain capability and potential fuel economy benefits for modern diesel engines operating in severe applications. Utilizes state-of-the-art technology to help deliver exceptional performance and is recommended for use in all super high-performance diesel applications, including modern low emission engine designs with Exhaust Gas Recirculation (EGR), as well as refrigerated units and well-maintained engines. This formula provides thermal and oxidative stability to help prevent high-temperature deposits and low-temperature sludge buildup. Its exceptional low temperature pumpability allows for easy engine start-up and helps to reduce wear. Mobil 1 Turbo Diesel Truck 5W-40 is recommended for use in a wide range of light-duty applications such as turbo diesel pick-up trucks, as well as heavy-duty applications and operating environments found in the on-road transport and off-road mining, construction, and agricultural industries. The performance of Mobil 1 Turbo Diesel Truck 5W-40 is the result of extensive cooperative development work with major equipment builders and application of the latest lubrication technology. Compared to a 15W-40 conventional engine oil. Actual savings are dependent upon vehicle/engine type, outside temperature, driving conditions, and your current engine oil viscosity.