Valvoline Synpower, QT, 75W140, Full Synthetic Gear Oil, Is Formulated For Ultimate Protection & Performance, A Thermally Stable, Extreme-Pressure Gear Lubricant, It Is Designed To Operate & Protect In Both High & Low Extreme Temperature Conditions, Specially Recommended For Limited Slip Hypoid Differentials & Is Compatible With Conventional Gear Lubricants.