AMSOIL Synthetic 15W-40
Heavy-Duty Diesel & Marine Oil

Controls Excessive Soot Loading Found in EGR-Equipped Engines

AMSOIL Synthetic 15W-40 Heavy-Duty Diesel and Marine Oil is heavily fortified with detergent/dispersant additives and is naturally resistant to soot. It keeps soot particles suspended independently, preventing them from attaching together to form larger, wear-causing particles. Viscosity increase is minimized and soot-related wear is controlled.

Excels in Extreme Temperatures

Unlike conventional petroleum oils, AMSOIL Synthetic 15W-40 Heavy-Duty Diesel and Marine Oil contains no wax. It stays fluid down to -44°F for improved cold-temperature oil flow, providing vital start-up lubrication for easier starts and reduced wear. AMSOIL 15W-40 Heavy-Duty Diesel and Marine Oil outperforms conventional 15W-40 petroleum oils and greatly minimizes the impact of cold-weather operation.

Eliminates the Need for Special Inventories of Seasonal Oils

AMSOIL Synthetic 15W-40 Heavy-Duty Diesel and Marine Oil will not shear back to a lower viscosity. This is especially important for engines that operate continually at constant speed, such as stationary engines, marine engines and farm tractors. Traditionally, such engines have been lubricated with high-viscosity single-grade oils, such as SAE 40, to avoid oil shear-back (which sometimes occurs with multi-viscosity oils using low-quality viscosity index improvers). However, single-grade oils are too thick to allow easy starting and quick engine lubrication in cold temperatures.
     AMSOIL 15W-40 Heavy-Duty Diesel and Marine Oil provides the high-temperature protection of an SAE 40 and the low-temperature pump ability of a 15W oil throughout its entire service life. All-season, all-temperature AMSOIL 15W-40 Heavy-Duty Diesel and Marine Oil eliminates the need for special inventories of seasonal oils.

One Million Miles Between Overhauls

AMSOIL Synthetic 15W-40 Heavy-Duty Diesel and Marine Oil's 12-TBN formulation keeps engines in superb condition, reducing wear, ring deposits and cylinder bore polish, even when the oil is used for extended drain intervals. Conventional oils break down and form deposits, which cause ring sticking and requires ring and liner replacement. With AMSOIL, truckers may realistically expect to travel one million miles between overhauls, saving maintenance costs.

Prevents Rust and Corrosion

AMSOIL Synthetic 15W-40 Heavy-Duty Diesel and Marine Oil contains special rust and corrosion inhibitors that protect engines from internal rust, which is especially important for marine engines or equipment that is stored long-term, such as farm equipment.

Less Foam Means Better Drivability

Some vehicles have been known to suffer drive-ability problems due to oil foaming. Foamy oil interferes with fuel injection, which reduces engine power. The ASTM D892 Foam Test, Sequences 2 and 4, are used to evaluate diesel oils on their foaming characteristics.
     According to test results, AMSOIL Synthetic Diesel Oils are clearly less prone to foaming (see graph). Not only are AMSOIL Synthetic Diesels Oils less prone to foaming, they also dissipate foam more quickly and excel in comparison to Shell Rotella T, a popular diesel oil often recommended by some engine manufacturers.

Outstanding All-Fleet Performance (Diesel and Gasoline Engines)

AMSOIL Synthetic 15W-40 Heavy-Duty Diesel and Marine Oil exceeds the performance specifications of all major American and European truck manufacturers. Though it is designed for diesel engines, it may also be used in gasoline-powered engines, so separate oils for diesel- and gasoline-powered equipment or vehicles are not needed.

409,000 Miles Without an Oil Change!

After 409,000 miles without an oil change, this AMSOIL-protected Mack E7-400 engine was as wear-free as an engine in comparable service treated to TWENTY TIMES the oil changes.

Suggested Reading: 409,000 Mile Oil Drain Interval Mack Engine Teardown

Extended Service Life

AMSOIL Synthetic 15W-40 Heavy-Duty Diesel and Marine Oil is a proven long-drain oil and can extend drain intervals far beyond those recommended for conventional oils. Its unique synthetic formulation and long-drain additive system deliver the best possible engine protection, cleanliness and performance over extended drain intervals, reducing vehicle maintenance and waste oil disposal costs.

AMSOIL Synthetic Heavy Duty Diesel & Marine Motor Oil is recommended for extended drain intervals in unmodified, mechanically sound vehicles or equipment as follows:

Personal light truck vehicles with diesel engines:

Normal Service: Up to 25,000 miles or one year, whichever comes first, or longer based on oil analysis.

Severe Service: Up to 15,000 miles or one year, whichever comes first, or longer based on oil analysis.

Commercial or fleet vehicles, long-haul trucks, marine craft, RVs/motor homes or off-road equipment with diesel engines:

Non-EGR equipped diesels: Up to two times the OEM (original equipment manufacturer) recommended drain interval or one year, whichever comes first, or longer based on oil analysis.

EGR equipped or low emission diesels: Extend drain intervals based on oil analysis or use the longest drain recommendation of the OEM (original equipment manufacturer).

Personal vehicles with gasoline engines:

Up to two times the OEM (original equipment manufacturer) recommended drain interval (not to exceed 15,000 miles without oil analysis) or one year, whichever comes first.

Please visit the AMSOIL Corporate website for more details on this product.

Oil Filter Service Intervals

Extended oil drain intervals are based on the user following AMSOIL recommended oil filter service intervals:

Personal light truck vehicles with diesel and gasoline engines:

If using an AMSOIL Ea™ or a Donaldson Endurance™ Oil Filter, install a new oil filter at time of oil change. AMSOIL Ea™ and Donaldson Endurance™ Oil Filters offer a 25,000-mile or one-year service life, whichever comes first.

If using other brands of oil filters, install a new oil filter at time of oil change then change at the engine manufacturer's recommended filter change intervals.

Commercial or fleet vehicles, long-haul trucks, marine craft, RVs/motor homes or off-road equipment with diesel engines:

If using an AMSOIL Ea™ or a Donaldson Endurance™ Oil Filter, install a new oil filter at time of oil change then change at two times the OEM standard interval, not to exceed 60,000 miles in long-haul trucks.

If using other brands of oil filters, install a new oil filter at time of oil change then change at the engine manufacturer's recommended filter change intervals.

Note: AMSOIL Ea™ Oil Filters are designed for extended drain intervals. They stop smaller particles, allow more oil flow and last longer than regular filters.

Applications

AMSOIL Synthetic 15W-40 Heavy-Duty Diesel and Marine Oil is engineered for use in a wide variety of light- and heavy-duty applications, including over-the-road trucks, off-road construction, marine engines, farm equipment, logging and mining equipment, stationary engines, generators, irrigation pumps. It is ideal for personal automotive or commercial transportation, such as taxi and local delivery fleets, with gasoline or diesel engines. It is excellent for use with low- or high-sulfur diesel fuels in standard, turbocharged or supercharged engines, including modern low-emission diesels such as those equipped with EGR systems. AMSOIL 15W-40 Heavy-Duty Diesel and Marine Oil is recommended for applications requiring the worldwide performance specifications listed on the AMSOIL Corporate website (see below).

Engine Protection Requirements

AMSOIL Synthetic Motor Oils meet or exceed specific API, ACEA and ILSAC service classifications and the engine protection requirements of various domestic and foreign engine manufacturers. Please visit the AMSOIL Corporate website for an up-to-date listing on this product.

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