Heavy-duty diesel pickup towing a livestock trailer outside a lit barn at dusk, a common AMSOIL diesel motor oil application

AMSOIL Diesel Motor Oil

Synthetic diesel oil built for Power Stroke, Cummins, and Duramax pickups as well as commercial fleets, with Signature Series Max-Duty, Heavy-Duty, and Freedom Series formulas.

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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Order AMSOIL Diesel Oil Online

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Diesel Motor Oil Products

Compare the full lineup below, then use the AMSOIL online lookup guide to confirm the formula and viscosity that fits your application.

AMSOIL Signature Series 0W-40 100% Synthetic Max-Duty Diesel Oil staged in a diesel truck shop

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 Signature Series 10W-30 100% Synthetic Max-Duty Diesel Oil staged in a diesel truck shop

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 staged in a diesel truck shop

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 staged in a diesel truck shop

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 staged in a diesel truck shop

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 10W-30 100% Synthetic Diesel Oil staged in a diesel truck shop

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 staged in a diesel truck shop

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 staged in a diesel truck shop

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.

AMSOIL 10W-30 Commercial-Grade Diesel Oil staged in a diesel truck shop

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.

AMSOIL 10W-30 Heavy-Duty 100% Synthetic Diesel Oil staged in a diesel truck shop

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 staged in a diesel truck shop

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 staged in a diesel truck shop

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.

AMSOIL 0W-20 100% Synthetic Diesel Oil staged in a diesel truck shop

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 staged in a diesel truck shop

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 staged in a diesel truck shop

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.

Whatever You Drive, However You Drive, AMSOIL Has You Covered