Gulf Western Marine Gear Oil 75W-90 is a Full Synthetic gear oil formulated for use in marine outboard gear cases and stern drive units fitted to a wide range of marine engines. This gear oil provides excellent cold start performance for smooth gear selection and engagement while also offering superb operating temperature protection. Gulf Western Marine Gear Oil 75W-90 is suitable for use where API GL-5, SAE 75W-90, 80W-90 and SAE 90 gear oils are recommended. To find the correct outboard gear oil type and weight suggested for your vessel; either check with your manufacturer, your local mechanic or head in-store and talk to one of our friendly team.