Mobil Synthetic Gear Oil 75W-90 is a fully synthetic gear lubricant formulated from synthetic base oils and an advanced additive system. It is designed for use in many railway gearboxes and provides excellent load-carrying capability where extreme pressures and shock loading are expected. This gear oil provides excellent thermal and oxidation stability, high Viscosity Index (VI), extremely low pour point, and low-temperature fluidity. Mobil Synthetic Gear Oil 75W-90 meets the API GL-5 performance level.