Shell Rotella T5 15W-40 Synthetic Blend diesel engine oil with Triple Protection Plus technology uses synthetic base oils plus advanced additive technology to provide protection against wear, deposits, and oil breakdown. Triple Protection Plus technology also provides better low-temperature flow, delivering excellent equipment protection and long engine life while maintaining viscosity control under high temperatures. Shell Rotella T5 15W-40 Synthetic Blend Technology works even harder than new CK-4 specifications require, delivering an average of 37% better wear protection than the maximum wear requirements (calculated average based on API CK-4 wear test results). Shell Rotella T5 15W-40 Synthetic Blend is suitable for a wide range of heavy duty engine applications. It is an excellent choice for on-highway fleets, construction, agriculture, and diesel pick-up trucks, including high-power vehicles where resistance to increased heat and stress is required. It provides all the protection you expect from an SAE 15W-40 but in a synthetic blend heavy duty engine oil.