Part Number: 50604. Red Line 50604 MT-LV is a full synthetic 70W/75W GL-4 manual transmission and transfer case gear oil — the lightest-viscosity GL-4 product in Red Line's manual transmission lineup, and the correct fluid for the growing class of OEM specifications requiring 70W or 70W/75W gear oil across Toyota, Lexus, BMW, Porsche, Aston Martin, Audi, Lamborghini, and many other platforms.