Red Line Oil 50104 is a case of 12 quarts of fully synthetic 75W-85 GL-5 gear oil. It is designed for performance/custom fitment, featuring additional friction modifiers for fuel efficiency. Not suitable for most manual transmissions or transaxles with synchronizers. Known for shear stability and reduced oxidation, it exceeds API GL-5 specifications. Formerly known as LightWeight Gear Oil, made in the United States.