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

Product code : ADPQTC-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

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
    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.
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  • 5 star rating
    15-40
    By  JEREMY,  a  Verified Buyer  from  S.Illnois  on  November 28, 2024
    Happy with the oil I change it at 5k.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Incredibly Happy!
    By  JORDAN,  a  Verified Buyer  from  TN  on  November 27, 2024
    This is the only oil I have ran in my truck since the day I bought it - the truck currently has 267,000 miles of all this oil in it. Very pleased!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Just use it.
    By  ANDREW,  a  Verified Buyer  from  California   on  November 19, 2024
    400,000+ miles on my Duramax thanks to this oil!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best 100% Synthetic Diesel Oil made
    By  WY216,  a  Verified Buyer  from  Big Horn, WY  on  November 17, 2024
    It is without a doubt the best engine oil made for diesel owners. The truck runs cleaner, cooler, and longer between oil changes. I highly recommend it! I have 260,000 miles on my Ford 6.0 without any oil-related problems.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Longevity
    By  Avalon ,  a  Verified Buyer  from  Us East Coast   on  November 16, 2024
    AMSOIL 15W40 has been the only oil used in my 1999 Cummins 6BT5.9 along with their filters. EVERY oil analysis from Blackstone has come back with zero negatives. I will always use AMSOIL products in my engines.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Use the best forged the rest
    By  WAYNE,  a  Verified Buyer  from  Stroudsburg pa  on  October 28, 2024
    There is no substitute. There is only one oil AMSOIL
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil synthetic
    By  PAT,  a  Verified Buyer  from  Ontario  on  July 07, 2024
    Fast shipping. Great oil. Will always run AMSOIL 100% synthetic
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Truck oil
    By  WALTER,  a  Verified Buyer  from  Fenton, MI  on  June 14, 2024
    Have used this for quite a few years and had great results. Will use it on this truck and more to come. Love this stuff.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Truck oil
    By  Jeff,  a  Verified Buyer  from  Overton NV  on  June 09, 2024
    Great oil
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?