Duragard SAE 40WT Single Grade Heavy Duty Engine & Transmission Oil is specially formulated with a select High Viscosity Index (HVI) Group-II Hydro-cracked base oils combined with potent detergent dispersants, anti-wear additives, anti-oxidants, defoamers, and pour point depressant compounds that provide superior low temperature fluidity and extraordinary high temperature film strength that simply can not be achieved using conventional mineral based oils. Duragard SAE 40WT Single Grade Heavy Duty Engine & Transmission Oil meets the performance requirements of typical of Allison C-4, Caterpillar TO-2 fluids, and the non-synthetic requirements typical of CD/GL-1 for Eaton / Fuller Road Ranger & Spicer / Dana transmissions. Meets the requirements of API CF and CF-2.