Quicksilver High Performance Gear Lube SAE 90 Quicksilver High Performance Gear Lube is a synthetic blend gear oil thats specifically designed and tested for marine applications. SAE 90 Gear Lube is manufactured to provide maximum protection for sterndrive and outboard lower unit gear cases. It is recommended for use in extreme conditions including high-speed and high-horsepower applications to extend gear service life. Quicksilvers SAE 90 High Performance Gear Lubes formula helps prevent failur