AMSOIL 75W-90 100% Synthetic Marine Gear Lube

  • Excellent gear and bearing protection, even when contaminated with 15% water1
  • Reduced friction and wear
  • Protection against rust and corrosion
  • Long seal life
  • Superior foam prevention

1Based upon AMSOIL testing of AMSOIL 75W-90 Synthetic Marine Gear Lube in ASTM 3233 and ASTM D892

Product Overview

Delivers exceptional wear protection, even when contaminated with up to 15 percent water.1 Extreme-pressure formulation controls damage from shock-loading caused by propeller cavitation. Excellent for fast-accelerating, high-horsepower boats. Protects against rust and corrosion. Keeps seals soft to minimize water leakage. Compatible with other synthetic and conventional oils. Use in fresh- and saltwater applications that require 75W-90 or 80W-90 gear lube and any of the specifications listed below, including lower units made by Mercury/ Mariner,* Johnson/Evinrude,* Bombardier,* Honda,* Yamaha,* Suzuki,* Force/US Marine,* Nissan,* Tohatsu* and Harbormaster;* sterndrives made by Mercruiser-Bravo,* OMC/Bombardier, Volvo-Penta,* Yanmar,* Konrad* and Marine Drive Systems;* V-drives made by Casale & Menkins;* bow thrusters made by Harbormaster Marine;* and transmissions made by ZF Marine Transmission.*

  • API GL-4, GL-5

PROTECTS AGAINST WEAR

  • Fortified with extreme-pressure (EP) additives for superior protection of fast-accelerating, high-torque/horsepower engines.
  • Protects against shock loading from cavitation of heavily loaded engines.
  • Delivers advanced outboard protection against power loss and gear wear, even with up to 15 percent water contamination.1

RESISTS RUST & FOAM

  • Designed to prevent rust and is compatible with aluminum, copper and brass alloys.
  • Resists foam despite water contamination to ensure a strong fluid film and excellent wear protection.
  • Promotes long seal life to help prevent water intrusion.

EASY-PACK EASES MAINTENANCE

  • Award-winning AMSOIL easy-pack reduces mess and hassle when changing lower-unit gear oil.
  • Eliminates the need to buy and store a messy gear-lube pump.

1 Based upon AMSOIL testing of AMSOIL 75W-90 Synthetic Marine Gear Lube in ASTM 3233 and ASTM D892.

*All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use.

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Product information checked: September 2026. Product formulations, specifications, applications, availability and published claims can change.
For the latest official information, consult the AMSOIL Corproate Website.

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