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AMSOIL Heavy-Duty Synthetic Diesel Oil | 4X Wear Protection, API CK-4

AMSOIL Heavy-Duty Synthetic Diesel Oil delivers 4X better wear protection and up to 66% less oil consumption than the API CK-4 standard. Broad OEM coverage for trucks and equipment. Available in 10W-30, 5W-40 and 15W-40.

AMSOIL Heavy-Duty Synthetic Diesel Oil | 4X Wear Protection, API CK-4: Every Product in the Line

Product Viscosity Details Shop
AMSOIL Heavy-Duty 10W-30 Synthetic Diesel Oil 10W-30 Details → Shop at AMSOIL.com →
AMSOIL Heavy-Duty 15W-40 Synthetic Diesel Oil 15W-40 Details → Shop at AMSOIL.com →

Formulated for Exceptional Diesel Engine Protection

AMSOIL Heavy-Duty Synthetic Diesel Oil is formulated for hard-working equipment. It is engineered to provide 4X better wear protection, giving you the edge to keep trucks and equipment operating at peak performance. It offers outstanding value and excellent protection for customers seeking an upgrade over conventional, synthetic-blend or competing synthetic diesel oils.

Choose Your Viscosity

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Heavy-Duty Engine Protection

Wear on rings and cylinder liners leads to increased oil consumption and loss of compression, resulting in reduced horsepower and fuel economy. Third-party testing shows AMSOIL Heavy-Duty Synthetic Diesel Oil delivers 4X more wear protection — based on the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222, using 10W-30 as the worst-case representation — to help maximize equipment life and reduce maintenance costs and downtime.

Viscosity Control

Formulated with advanced synthetic base oils and detergent/dispersant additives, AMSOIL Heavy-Duty Synthetic Diesel Oil minimizes viscosity change while keeping soot particles suspended independently, helping prevent the formation of larger, wear-causing particles. Lower volatility also helps it retain viscosity after high-temperature service.

Excels in Extreme Temperatures

AMSOIL Heavy-Duty Synthetic Diesel Oil is formulated to deliver improved heat and oxidation resistance compared to conventional diesel oils. It provides clean engine operation and helps maintain power and fuel efficiency, and flows dependably in cold temperatures for easier startup and improved engine protection.

Minimizes Oil Consumption

AMSOIL Heavy-Duty Synthetic Diesel Oil has a low rate of volatility (burn-off), reducing oil consumption during operation. It provides up to 66 percent less oil consumption than required by the API CK-4 standard in the Caterpillar-1N oil consumption test.

Applications and Specifications

All three viscosities meet API CK-4, CJ-4, CI-4+, CF and a broad range of OEM specifications:

  • Volvo VDS4.5, VDS4, VDS3
  • Mack EOS-4.5, EO-O
  • Renault RLD-4, RLD-3
  • Cummins CES20086, CES20081
  • Caterpillar ECF-2, ECF-3, ECF-1-a
  • Detroit Diesel DDC 93K218, 93K215, 93K214; DFS 93K222
  • ACEA E9, E7
  • Mercedes-Benz 228.31 • MAN 3575 • MTU Type 2.1, II, I
  • JASO DH-2 • Deutz DQC III-10LA
  • Chrysler MS 10902 • Ford WSS-M2C171-F1

The 5W-40 and 15W-40 grades also carry API CF-2 and Allison TES439; the 5W-40 additionally carries JASO MA and MA2. All viscosities are capable of gasoline service API SN — consult your owner’s manual for the proper viscosity recommendation.

Service Life

Recommended for the drain intervals stated by the original equipment manufacturer (OEM). Refer to the owner’s manual for the specific oil change interval. Intervals may be extended beyond the OEM-recommended interval with oil analysis.

Order AMSOIL Heavy-Duty Synthetic Diesel Oil

Give hard-working diesel equipment 4X wear protection.

Shop Heavy-Duty Synthetic Diesel Oil at AMSOIL.com Independent AMSOIL Dealer #1858536

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Frequently Asked Questions

AMSOIL Product Warranty

Using AMSOIL synthetic lubricants or practicing extended drain intervals does not void your new vehicle or equipment manufacturer warranty. All AMSOIL lubricants and filters are covered by the AMSOIL Limited Warranty. For complete information visit AMSOIL.com/guarantee.


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Frequently Asked Questions

How much wear protection does AMSOIL Heavy-Duty Synthetic Diesel Oil provide?

Third-party testing shows it delivers 4X more wear protection — based on the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222, using 10W-30 as the worst-case representation.

Does it reduce oil consumption?

Yes. Its low rate of volatility provides up to 66 percent less oil consumption than required by the API CK-4 standard in the Caterpillar-1N oil consumption test.

Can I use it in a gasoline engine?

All viscosities are capable of gasoline service API SN. Consult your owner's manual for the proper viscosity recommendation for your engine.

How often should I change it?

It is recommended for the drain intervals stated by the original equipment manufacturer (OEM). Intervals may be extended beyond the OEM-recommended interval with oil analysis.

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