AMSOIL Signature Series 0W-40 100% Synthetic Max-Duty Diesel Oil
AMSOIL Diesel Motor Oil
Cold-weather grade of the Signature Series Max-Duty diesel line, formulated for severe-cold starting without giving up heavy-duty performance.
AMSOIL products
AMSOIL Diesel Motor Oil
Synthetic diesel motor oil for pickups, commercial trucks, fleet equipment, and heavy-duty diesel engines.
AMSOIL diesel oil
Compare AMSOIL diesel motor oil for Ford Power Stroke, Ram Cummins, GM Duramax, and heavy-duty fleet diesels, including Signature Series Max-Duty, Heavy-Duty, Commercial-Grade, and Freedom Series options in common diesel viscosities.
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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.
Signature Series
AMSOIL Signature Series 10W-30 100% Synthetic Max-Duty Diesel Oil
AMSOIL Diesel Motor Oil
Fuel-economy-focused heavy-duty engine oil engineered for modern emissions-equipped diesels and mixed fleets that allow a 10W-30 grade.
AMSOIL Signature Series 15W-40 100% Synthetic Max-Duty Diesel Oil
AMSOIL Diesel Motor Oil
Top-tier synthetic oil engineered for hard-working on-road and off-road diesel engines. Built from synthetic base oils with a boosted detergent.
AMSOIL Signature Series 5W-30 100% Synthetic Max-Duty Diesel Oil
AMSOIL Diesel Motor Oil
Top-tier synthetic diesel oil engineered for modern turbodiesel pickups, heavy-duty on- and off-road diesels, and engines.
AMSOIL Signature Series 5W-40 100% Synthetic Max-Duty Diesel Oil
AMSOIL Diesel Motor Oil
Top-tier synthetic motor oil for late-model emissions-compliant turbodiesel pickups, European diesel cars, and heavy-duty on- and off-road engines.
Freedom Series
Freedom Series 10W-30 100% Synthetic Diesel Oil
AMSOIL Diesel Motor Oil
Fuel-economy-focused heavy-duty grade co-developed by AMSOIL and Fleece Performance Engineering for turbodiesel pickups.
Freedom Series 15W-40 100% Synthetic Diesel Oil
AMSOIL Diesel Motor Oil
Workhorse heavy-duty grade in the AMSOIL Freedom Series line, co-developed with Fleece Performance Engineering for late-model turbodiesel pickups that tow.
Freedom Series 5W-40 100% Synthetic Diesel Oil
AMSOIL Diesel Motor Oil
Advanced full-synthetic diesel formulation co-developed by AMSOIL and Fleece Performance Engineering for turbodiesel pickups.
Commercial-Grade
AMSOIL 10W-30 Commercial-Grade Diesel Oil
AMSOIL Diesel Motor Oil
Advanced synthetic-blend heavy-duty engine oil formulated with greater than 50 percent synthetic content for on-road and off-road diesel service.
Heavy-Duty
AMSOIL 10W-30 Heavy-Duty 100% Synthetic Diesel Oil
AMSOIL Diesel Motor Oil
Fully synthetic heavy-duty diesel oil engineered for fleet trucks, work pickups, agricultural, and construction equipment.
AMSOIL 15W-40 Heavy-Duty 100% Synthetic Diesel Oil
AMSOIL Diesel Motor Oil
Workhorse SAE 15W-40 grade in the AMSOIL diesel lineup, formulated for over-the-road tractors, work pickups, agricultural, and construction equipment.
AMSOIL 5W-40 Heavy-Duty 100% Synthetic Diesel Oil
AMSOIL Diesel Motor Oil
Fully synthetic diesel engine oil engineered for hard-working pickups, fleet trucks, and equipment that operate across wide temperature swings.
Viscosity-Based Formulas
AMSOIL 0W-20 100% Synthetic Diesel Oil
AMSOIL Diesel Motor Oil
Fully synthetic light-duty diesel engine oil built for smaller American diesel pickups, vans, cars, and SUVs that specify a GM.
AMSOIL 15W-40 Commercial Grade Diesel Oil
AMSOIL Diesel Motor Oil
Advanced synthetic-blend heavy-duty diesel oil with greater than 50 percent synthetic content.
AMSOIL 5W-30 100% Synthetic Diesel Oil
AMSOIL Diesel Motor Oil
Light-duty synthetic diesel oil engineered for the smaller, efficient diesel engines fitted to American diesel pickups, vans, cars, and SUVs.