Quicksilver 85W-90 Extreme Performance Gear Lube - 1 Gallon, High-Strength Marine & Racing Protection

This premium 1-gallon lubricant delivers robust protection for outboard and sterndrive lower units and other high-stress gearboxes. Engineered and validated to Mercury Marine original equipment standards, this formulation emphasizes film strength, shear resistance and water tolerance so gears maintain torque transfer and resist accelerated wear in racing and demanding recreational use.

How does this gear lube protect gears under racing conditions?

Under high loads and elevated temperatures, gear surfaces face increased friction and risk of surface distress. The Quicksilver 85W-90 blends pressure additives and tackifiers that form a resilient lubricating film across teeth and bearings, helping preserve gear geometry and reduce metal-to-metal contact.

• Pressure additives increase load-carrying capacity during shock and high torque events
• Tackifiers improve film adhesion so oil stays where it’s needed
• High-temperature stability resists viscosity breakdown at racing heat levels

Can this be used if water gets into the gear housing?

Marine environments can expose gear oil to water intrusion from seals, splashes or condensation. This lubricant contains emulsifiers and dispersant technology that help maintain protection when minor water contamination occurs, supporting continued lubrication until service.

• Advanced emulsifiers assist in separating and managing water within the lubricant
• Helps sustain protective film rather than allowing rapid corrosion or rusting
• Designed for marine applications where occasional water exposure is possible

What maintenance schedule should I follow with this 1-gallon oil?

Routine replacement prolongs gearbox life and prevents buildup of contaminants that reduce protection. For seasonal recreational use, plan to replace gear lube annually when winterizing or follow an interval of approximately every 100 operating hours for high-use or racing applications.

• Change oil at least once per year during winterization
• For heavy or racing use, consider replacement every 100 hours
• Inspect seals and drain plugs when servicing to minimize future water ingress

Which gearcases and vehicles are compatible with this oil?

This 85W-90 formulation is intended for high-performance outboard and sterndrive gearcases and is also suitable for other powersports and motorsports gearboxes requiring an 85W-90 GL-grade lubricant. Confirm your manufacturer’s recommended viscosity and specs before use to ensure proper compatibility.

• Optimized for outboard and sterndrive racing lower units
• Appropriate for high-performance gear cases in marine and powersports equipment
• Formulated to meet or exceed Mercury Marine original equipment testing standards

Who is this for: This Quicksilver 85W-90 Extreme Performance Gear Lube is aimed at boat owners, racers, and powersports enthusiasts who demand durable protection for high-stress gear systems. It suits mechanics and DIYers servicing lower units or high-performance gearcases who want an OEM-developed product with proven film strength, water-handling capability and thermal stability. Choose this product if you need a gallon-sized supply for multiple services or frequent maintenance intervals and want the assurance of Mercury Marine research and testing behind the formula.