AMSOIL 25W-40 Synthetic-Blend Marine Engine Oil
AMSOIL Marine Oil
Four-stroke marine grade formulated for gasoline-fueled inboards, sterndrives, inboard/outboards, and personal watercraft.
AMSOIL products
AMSOIL Marine Oil
Marine synthetic oils and lubricants for outboards, inboards, personal watercraft, and boat gearcases.
AMSOIL marine oil
Buy AMSOIL marine oil for outboards, inboards, sterndrives, personal watercraft, and boat gearcases. HP Marine and 100:1 Pre-Mix cover TC-W3 two-stroke outboards, with Synthetic Marine Gear Lube for the lower unit.
Order online, or save up to 25 percent on every order by joining the AMSOIL Preferred Customer program for $20 USD per year. For local pickup, the order online covers the AMSOIL Dealer locator and how to find AMSOIL near you.
Add an AMSOIL Preferred Customer membership to the same cart to unlock up to 25% off qualifying products. Existing members can sign in, and qualifying orders currently over $100 can ship free.
Shop by Product Type
Start with a product family, then use the AMSOIL online lookup guide to choose the formula and viscosity that fits your application.
Synthetic-Blend
Heavy-Duty
AMSOIL 15W-40 Heavy-Duty Diesel and Marine Oil
AMSOIL Marine Oil
100% synthetic dual-purpose SAE 15W-40 lubricant for pre-emissions on-road and off-road diesels, marine diesel inboards.
Viscosity-Based Formulas
AMSOIL 10W-30 100% Synthetic Marine Engine Oil
AMSOIL Marine Oil
Premium synthetic 4-stroke formulation built for gasoline-fueled inboards, outboards, sterndrives, supercharged watercraft.
AMSOIL 10W-40 100% Synthetic Marine Engine Oil
AMSOIL Marine Oil
Premium synthetic four-stroke marine formulation built for gasoline-fueled inboards, outboards, sterndrives, supercharged watercraft engines.