The best choice for the 5. 9 Cummins is AMSOIL SAE 15W-40 Heavy-Duty Diesel and Marine Motor Oil . I change the filter every 5,000 miles and drain and refill with fresh oil one a year. I'll pull the valve cover off in 2022 for the 1st time, and there will be just a light coating of oil on the inside of the cover.
Engineered for pre-2007 diesel engines in on-road applications as well as all model year diesel engines in off-road applications. High 12 TBN controls acids from combustion blow-by and EGR. Additives control soot thickening, oxidation and wear. Extended drain capabilities reduce downtime and motor oil expenses.
AMSOIL Synthetic Heavy Duty Diesel & Marine Motor Oil (AME) is a premium diesel oil providing excellent performance in all types of diesel engines where highly effective control of wear and deposits is vital. Built with heavy-duty dispersant/detergent additives, its 12 TBN chemistry neutralizes acids and controls soot thickening from EGR and blow-by to protect against corrosion, cylinder bore polishing (wear) and varnish/sludge deposits. AMSOIL 15W-40 Diesel Oil resists heat and breakdown better than conventional petroleum oils for long lasting performance and protection.
AMSOIL, the leader in automotive synthetic lubrication, produced the world’s first API qualified synthetic motor oil in 1972. Trust the extensive experience of AMSOIL The First in Synthetics ® to do the best job protecting your engine.
Extends Drain Intervals
AMSOIL Synthetic Heavy Duty Diesel & Marine Motor Oil can extend drain intervals far beyond those recommended for conventional petroleum oils. Its unique synthetic formulation and long-drain additive system deliver maximum engine protection, cleanliness and performance over extended drain intervals, reducing vehicle maintenance and waste oil disposal costs.
Advanced Soot and Wear Control Formula
AMSOIL Synthetic Heavy Duty Diesel & Marine Motor Oil is heavily fortified with detergent/dispersant additives and is naturally resistant to soot. It is designed to keep soot particles suspended independently and prevent them from attaching together to form larger, wear-causing particles. Viscosity increase is minimized and soot-related wear is controlled.
Maximizes Fuel Economy, Reduces Oil Consumption and Emissions
AMSOIL Diesel & Marine Motor Oil has lower volatility (evaporation) than con-ventional petroleum oils. Because less oil vapor passes into the combustion chamber, oil consumption and emissions are reduced. Lower volatility helps AMSOIL 15W-40 Diesel Oil retain its viscosity after high-temperature service for excellent fuel economy and continued dependable protection.
Excellent Cold Flow Properties
AMSOIL AME remains fluid down to -44°F. It eases cold-weather starting and provides vital start-up lubrication to prevent engine wear. AMSOIL Synthetic Heavy Duty Diesel Oil outperforms conventional 15W-40 petroleum oils and greatly minimizes the impact of cold weather operation.
APPLICATIONS
AMSOIL Synthetic Heavy Duty Diesel & Marine Motor Oil is engineered for use in a wide variety of light and heavyduty applications, including over-the-road trucks, off road construction, marine engines, farm equipment, mining, industrial (pumps & generators) and personal automotive or commercial transportation. 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 Synthetic Heavy Duty Diesel & Marine Motor Oil is recommended for use in diesel engines and other applications requiring any of the listed worldwide specifications and gasoline engines requiring API SL, SJ, SH… or ACEA A3.
* API CI-4+, CF, CF-2, SL, SJ, SH
* ACEA A3/B3, E2, E3, E5, E7
* Global DHD-1
* JASO DH-1
* Mack EO-M+ EO-N Premium Plus '03
* DDC Power Guard 93K214
* Caterpillar ECF-1A, ECF-2
* Cummins CES 20071, 20072, 20076, 20077, 20078
* Volvo VDS-2, VDS-3
* MB 228. 3, 229. 1
* MAN 271/3275
* MTU Type 2
* Allison C-4
MIXING AMSOIL
AMSOIL AME is compatible with conventional and synthetic motor oils. Mixing AMSOIL motor oils with other oils, however, will shorten the oil life expectancy and reduce the performance benefits. AMSOIL does not support extended drain intervals where oils have been mixed.
Aftermarket oil additives are not recommended for use with AMSOIL motor oils.
SERVICE LIFE
AMSOIL Synthetic 15W-40 Heavy Duty Diesel and Marine Motor Oil (AME) is recommended for extended drain intervals in engines that are unmodified and in good operating condition.
Diesel Engine Service
* Three times (3X) OEM* recommendation, not to exceed 50,000 miles/600 hours or one year, whichever comes first. Drain intervals may be extended further with oil analysis.
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