Description Mobil Delvac 1 Gear Oil 75W-90 is a  fully synthetic drivetrain lubricant engineered to meet very demanding extended drain and warranty requirements. This product is designed for use in heavy-duty drivetrains that require gear lubricants with excellent load-carrying capability and where extreme pressures and shock loading are expected.  Mobil Delvac 1 Gear Oil 75W-90 incorporates synthetic basestock and advanced additives providing significant advantages over conventional gear oils. The state-of-the-art technology in Mobil Delvac 1 Gear Oil 75W-90 delivers excellent performance, helps to protect against thermal degradation and oxidation, contributes to reduced wear and corrosion, improved shear stability and extended service capability.