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The First In Synthetics
Motor Oil For Boaters


The Right Choice For Outboards
Made For Marine Environment
Excellent anti-rust performance
EXTENDS ENGINE LIFE
Less likely to acidify and oxidize
INCREASE FUEL EFFICIENCY
Smoother running motors use less fuel
- Protects Engines During Use And During Inactivity or Long-Term Storage
- Fortified With Potent Rust Inhibitors That Guard Against Rust And Corrosion
- Excellent High-Stress, High-RPM Endurance

Extends Outboard Motor Life

- Protects Engines During Use And During Inactivity or Long-Term Storage
- Fortified With Potent Rust Inhibitors That Guard Against Rust And Corrosion
- Excellent High-Stress, High-RPM Endurance
Product Details and Specifications

- 10W-30 & 10W-40 Marine Oil Weights
- NMMA FC-W Catalyst Compatible
- Technical Data Sheets
- Sold In Quart, 12-Quart Cases and More
- ISO 9001/14001 Registered
- Warranty

We stand by our products
IN DEPTH
Fights Engine Wear
AMSOIL Synthetic Marine Engine Oil’s naturally strong base oils resist viscosity loss due to mechanical shear. It develops a tough lubricating film that protects engine parts, even in high-heat, high-rpm conditions that breakdown other oils. Synthetic Marine Engine Oil contains robust anti-wear additives that further reduce wear in metal-to-metal contact regions, guarding against compression loss for maximum power and engine life.
Excellent Anti-Rust Performance
Good rust protection is not natural to motor oil; it comes only by design. AMSOIL Synthetic Marine Engine Oil is fortified with potent inhibitors that guard against damaging rust and corrosion. It protects engines during use and during inactivity or long-term storage.
NMMA Certified
AMSOIL Synthetic Marine Engine Oil is certified by the National Marine Manufacturers Association (NMMA) for use in four-stroke outboard motors. This high-quality oil demonstrates outstanding performance and meets the requirements of the NMMA FC-W Catalyst Compatible specification, which is backward-compatible with the FC-W specification.
We stand by our products