AMSOIL Synthetic 15W-40 API-CJ-4 Diesel Oil

February, 2017- This product has been replaced by AMSOIL Signature Series 15W-40 Max-Duty Synthetic Diesel Oil


Synthetic 15W-40 Diesel Oil Package sizes include:
1-Quart Bottle (or buy case of 12)
1-Gallon Bottle (or buy case of 4)
2.5-Gallon Bottle (or buy in twin pack)
30-Gallon Drum
55-Gallon Drum
275 Gallon Tote


Oil Depot can offer AMSOIL Synthetic 15W-40 Diesel Oil at wholesale prices in Canada or the United States. Request a price list using the contact form on your right.

AMSOIL Synthetic 15W-40 Diesel Oil is suitable for 2007 and newer diesel engines requiring the API “CJ-4” specification. It is also an outstanding synthetic oil for older diesel units built prior to 2007.

Features and Benefits of AMSOIL Premium Synthetic API “CJ-4” 15W-40 Diesel Oil

  • Lowers friction for improved fuel mileage and maximum wear control
  • Withstands hot operating temperatures and heavy loads
  • This 15W-40 synthetic oil provides excellent cold-cranking protection with a cold-pour-point of -40C (-40F)
  • Capable of staying in service for up 3 times the recommended oil change interval in pre-2007 units
  • Lowers oil consumption due to low volatility

Compatible with Modern Diesel Exhaust Treatment Devices

This API CJ-4 15W-40 diesel engine oil is compatible with all late-model exhaust treatment units including diesel particulate filters.

Saves Money with Long Oil Change Intervals

AMSOIL Synthetic 15W-40 Diesel Oil’s synthetic formula and generous additive package is designed for oil change intervals up to 3 times that as recommended by OEM’s. For fleets, synthetic diesel oil can save thousands of dollars per year. Due to fuel dilution issues, some models manufactured after 2007 have to follow OEM-recommended service intervals. See “Service Life” below.

Keeps Soot Under Control

Soot can be a major scourge in diesel engine crankcases. It can cause the engine oil to thicken and can also increase engine wear. The premium formula of our AMSOIL 15W-40 Synthetic Diesel Oil is loaded with detergents and dispersants that keep soot in suspension and your engine internals clean. A heavy-duty additive package like this is what separates premium synthetic diesel engine oils from the economy brands.

Curbs Oil Usage

Oil burning can occur when the volatility limits of diesel engine oil are tested under hot operating conditions or heavy loads. The robust formula of our AMSOIL Synthetic 15W-40 Synthetic Diesel Oil can withstand extreme heat and deliver exceptional volatility resistance. The result is minimal oil usage and lowered emissions due to less oil burning.

Suitable for a Most All Diesel Trucks and Equipment

AMSOIL Premium CJ-4 15W-40 Synthetic Diesel Oil covers a wide spectrum of applications making it a convenient choice for fleets looking to consolidate their oil needs. This synthetic diesel oil has the ability to extend drain intervals and improve fuel economy and help reduce maintenance costs.

AMSOIL Synthetic Diesel Oil Applications

AMSOIL Premium CJ-4 Synthetic 5W-40 Diesel Oil is suitable for the following diesel engine oil specifications:

  • API CJ-4, CI-4+, CF, SM
  • ACEA E7, E9
  • Mack EO-O
  • DDC 93K218
  • Caterpillar ECF-3, ECF-2, ECF-1a
  • Cummins CES 20081
  • Volvo VDS-4, VDS-3
  • MB 228.31
  • MS10902
  • MTU Type I, II & 2.1
  • MAN 3275, 3575
  • JASO DH-2
  • Global DHD-1
  • Renault RLD-3

Mixing AMSOIL Synthetic Diesel Oil with Other Brands

AMSOIL Synthetic 15W-40 Diesel Oil is compatible with all other brands of conventional and synthetic engine oils. While you can safely mix AMSOIL Synthetic Oil with other oil brands, this will reduce the drain interval and performance capabilities of the AMSOIL oil.

The use of any aftermarket oil additives is definitely not recommended.

Service Life

AMSOIL Premium Synthetic 15W-40 Diesel Oil is recommended for extended drain intervals in mechanically-sound pre-2007 engines that are in stock form.

Diesel Engine Oil Life Recommendations

  • 2007 and newer: Dodge/Cummins 6.7L, Ford PowerStroke 6.4L, GM Duramax 6.6L pickup engines must follow the manufacturer’s oil change interval. This is due to excessive fuel dilution.
  • Pre-2007 units: Up to three times the oil change interval as recommended by your owner’s manual. Must not exceed 50,000 miles (80,000 km) or 600 hours or one year.
  • 2007- 2009 Caterpillar C13 and C15 highway engines must follow the manufacturer’s oil change interval. This is due to excessive fuel dilution.

Note: When using 5% biodiesel (B5), follow the manufacturer’s oil change interval or support with oil analysis.

Gasoline Engine Oil Life Recommendations

Up to two times the oil change interval as recommended by your owner’s manual to maximum of 15,000 miles (24,000 km) or one year, whichever comes first.

Note: When using gasoline with an ethanol content of greater than 10%, follow the manufacturer’s oil change interval or support with oil analysis.

Specifications of AMSOIL 15W-40 Premium Synthetic Diesel Oil

Kinematic Viscosity @ 100°C, cSt (ASTM D-445)


Kinematic Viscosity @ 40°C, cSt (ASTM D-445)


Viscosity Index (ASTM D-2270)


CCS Viscosity @ -30°C, cP (ASTM D-5293)


Flash Point °C (°F) (ASTM D-92)

238 (460)

Fire Point °C (°F) (ASTM D-92)

254 (489)

Pour Point °C (°F) (ASTM D-97)

-40 (-40)

Noack Volatility (DIN 51581) 250°C for 1 hour, % weight loss


Four-Ball Wear Test (ASTM D-4172: 40kgf, 75°C, 1200 rpm, 1 hr) Scar diameter, mm


Total Base Number


High Temperature/High Shear Viscosity, cP (ASTM D-4683)


Sulfated Ash Content, wt. %


AMSOIL Premium CJ-4 Synthetic 15W-40 Diesel Oil
An elite synthetic CJ-4 15W-40 diesel motor oil suitable for year-round use. This synthetic diesel oil lowers friction for improved fuel mileage and reduced engine wear.
Manufacturer: AMSOIL
Model: Premium CJ-4 Synthetic 15W-40 Diesel Oil
Product ID: DME