Shell Rotella T4 Triple Protection 15W-40 is designed to provide hardworking protection that adapts to your driving conditions. With millions of miles of real world testing, Shell Rotella T4 Triple Protection 15W-40 uses a proprietary formula exclusive to Shell. It is designed to protect under the most severe engine conditions found in modern low emission engines and older hard working diesel engines. It is designed to effectively sustain emissions control system durability where diesel particulate filters and after-treatment systems are used. Plus it provides enhanced protection against viscosity loss due to shear and improved oil aeration. The exclusive low ash formulation helps protect the exhaust catalysts and diesel particulate filters found on the latest low emission vehicles. Suitable for virtually all modern low emission heavy-duty engines and older hard working diesel engines.