LUBRIGUARD Synthetic SAE 40 Heavy Duty Manual Transmission Fluid is a specially formulated synthetic lubricant designed for fuel efficiency, extended drain intervals and severe service in heavy duty commercial vehicle transmissions which require a non-EP transmission lubricant. It is specially formulated to protect high torque transmissions coupled with increased horsepower engines. It is approved for use in Eaton transmissions such as Ultrashift Plus, Fuller Advantage, FR and RT Series transmissions. It is not suitable for hypoid gear applications in differentials and final drives, either for topping-off or refills, where API Service GL-5 or SAE J2360 lubricants are specified.