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AMSOIL 15W-40 Heavy-Duty 100% Synthetic Diesel Oil

Product code : ADP1G-EA

  • Delivers 4X more wear protection1
  • Minimizes oil consumption
  • Excels in extreme temperatures
  • Helps keep trucks and equipment operating at peak performance
  • Offers outstanding value

    1Based on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 10W-30 as worst-case representation

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AMSOIL 15W-40 Heavy-Duty 100% Synthetic Diesel Oil



Developed to provide protection beyond conventional, synthetic-blend and other synthetic oils. AMSOIL synthetic technology delivers heavy-duty protection for diesel enthusiasts and those who depend on their trucks and equipment to make a living.

See the Product Data Bulletin for full details.


HEAVY-DUTY ENGINE PROTECTION

  • Delivers 4X more wear protection1
  • Helps maximize equipment life
  • Helps reduce maintenance costs and downtime

1Based on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 10W-30 as worst-case representation

Delivers More Wear Protection

Third-party testing shows Heavy-Duty Synthetic Diesel Oil delivers 4X more protection against wear than required by Detroit Diesel’s* standard.I

IBased on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 10W-30 as worst-case representation. *All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use.


VISCOSITY CONTROL

  • Resists oxidation and the thickening effects of soot contamination
  • Retains viscosity after high-temperature service for added engine protection and increased fuel economy
  • Provides up to 66 percent less oil consumption2

2Than required by the API CK-4 standard in the Caterpillar-1N oil consumption test

Reduces Oil Consumption

Heavy-Duty Synthetic Diesel Oil provides up to 66% less oil consumption.L

Reduces Oil Consumption – Heavy-Duty Synthetic Diesel Oil provides up to 66% less oil consumption.

L Than required by the API CK-4 standard in the Caterpillar-1N oil consumption test.


EXCELS IN EXTREME TEMPERATURES

  • Provides outstanding protection and performance in hot and cold temperature extremes
  • Delivers improved heat and oxidation resistance compared to conventional diesel oils
  • Flows dependably in cold temperatures for easier startup and improved engine protection

See the Product Data Bulletin for full details.

AMSOIL 15W-40 Heavy-Duty 100% Synthetic Diesel Oil

Data Bulletin

Warranty

SDS



AMSOIL 15W-40 Heavy-Duty 100% Synthetic Diesel Oil

  • 5 star rating
    Best oil on the Market!
    By  Jim,  a  Verified Buyer  from  CA  on  January 19, 2025
    I have used 15-40 in my Chevy Duramax since I bought it, quieted it down, lowered temps and overall exceeded my expectations!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product made in USA !
    By  KERRY,  a  Verified Buyer  from  Oregon   on  January 18, 2025
    Great company great product speedy delivery made in the USA!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Great for my 07 5.9 Cummins
    By  BRAD,  a  Verified Buyer  on  January 14, 2025
    I do one oil change a year on my 2007 Dodge Cummins, and this oil is just incredible. Probably a little overkill for the annual mileage but worth every penny.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The good stuff
    By  LUKE,  a  Verified Buyer  on  January 13, 2025
    Best of the best
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  PETER,  a  Verified Buyer  from  Given   on  January 01, 2025
    This oil is a great price and i recommend this product
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best Oil you can buy
    By  NATHEN,  a  Verified Buyer  on  December 27, 2024
    This oil is the best you can get. I trust it with all my engines which include diesel, gas and outboard boat. Can’t go wrong with their oil and their other products.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best oil out there. Better than Mobile one in my opinion
    By  JOHN,  a  Verified Buyer  from  700 holly hills   on  December 19, 2024
    See above
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent performance and long lasting.
    By  ECODiesel,  a  Verified Buyer  from  Oklahoma   on  December 07, 2024
    Been running this in my Ram 2500 with the cummins for a while. Oil stays clean and if you run a bypass system you can run this oil for 20K plus miles.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best Synthetic oil out there!
    By  WENDELL,  a  Verified Buyer  from  utah  on  December 06, 2024
    I put Amsoil in everything I own. People complain about the cost, but I can go 1 year+ between oil changes in my Duramax Diesel. People don't realize engines with turbos break down oils a lot quicker because of the intense heat (1700 degrees). Oil circulates through the turbo, Amsoil does not break down like other oils in that kind of temperature.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Review
    By  RICHARD,  a  Verified Buyer  from  Ca.  on  December 01, 2024
    Have used Amsoil in my Dodge Cummings engine for seven (7) years. Maintains higher oil pressure at an idle than other engine oils. When having the injectors and valves adjusted, my mechanic tells me my upper engine is the cleanest he has ever see that has 228,000 miles on it. Rich Aubuchon owner
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?