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AMSOIL 5W-40 Heavy-Duty 100% Synthetic Diesel Oil

Product code : ADOQTC-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 5W-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 5W-40 Heavy-Duty 100% Synthetic Diesel Oil

Data Bulletin

Warranty

SDS



AMSOIL 5W-40 Heavy-Duty 100% Synthetic Diesel Oil

  • 5 star rating
    Best oil for diesel
    By  CHRIS,  a  Verified Buyer  on  April 16, 2025
    Great oil for the Cummins
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good product
    By  CALEB,  a  Verified Buyer  from  NC  on  April 12, 2025
    Really like the product and will keep using from now on and will use other products in the future
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great stuff
    By  JIM,  a  Verified Buyer  on  April 05, 2025
    This is the besr stuff you can use. Can't beat the price hello
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    2004 Chevrolet 2500 H D
    By  DAN,  a  Verified Buyer  from  WY  on  April 05, 2025
    I experimented amsoil a few years ago, Then more technology came aboard , with synthetic....oils for everything.... With vehicles selling for $ 1,000,000 , even parts.... With your help parts last longer.... Thank You...
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil Quality
    By  WILLIAM,  a  Verified Buyer  from  FL  on  April 03, 2025
    High product quality aside, I always appreciate the service and how fast and reliable it is. Where I'm at i can have anything from Amsoil second business day on my doorstep. Free shipping
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Customer service
    By  TIM,  a  Verified Buyer  on  April 03, 2025
    Great products but customer service not so much
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    amsoil synthetic oils
    By  DAVID,  a  Verified Buyer  from  california  on  April 02, 2025
    I have been using Amsoil products 20 years. I have not found a better product for all my vehicles.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    100%
    By  REGINO,  a  Verified Buyer  from  Bensenville   on  April 01, 2025
    Nice and easy to order good product no problems on my orders before tanks por your service
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Good
    By  CARLOS,  a  Verified Buyer  from  New mexico  on  March 28, 2025
    My first order was the hole oil change kit with filter for my 2021 GMC 2500 AT4. The oil is great but the only thing that I really disliked, is the I was sent the wrong oil filter. So I had to go buy a different one right after I started the oil change. That was very frustrating, and disappointing. But otherwise a good product, I won’t be buying the whole kit again.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Sticks well
    By  COLLIN,  a  Verified Buyer  from  Maryland   on  March 28, 2025
    Use this in an 02 Duramax, has a sticks well to metal surfaces.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?