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Heavy-Duty Synthetic Diesel Oil 5W-40

Product code : ADOQT-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

  • 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

Warning - Click here for Proposition 65 information for this product

Heavy-Duty Synthetic Diesel Oil 5W-40



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.

Heavy-Duty Synthetic Diesel Oil 5W-40

Data Bulletin

Warranty

SDS



Heavy-Duty Synthetic Diesel Oil 5W-40

  • 5 star rating
    Great oil. Great program
    By  JASON,  a  Verified Buyer  from  Calgary Alberta   on  May 29, 2023
    Been using Amsoil for about 8 years now in various vehicles. What drew me in was the product quality and reputation. I work a lot in remote areas and don't always have access to power for my block heater. Extreme cold weather starts have been made easier since I switched to the 5w-40.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Awesome
    By  AUGUST,  a  Verified Buyer  from  Isabella mn  on  April 28, 2023
    The best Diesel motor oil I have ever used it’s awesome
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Feels Good
    By  BRANDON,  a  Verified Buyer  on  April 13, 2023
    It just feels good knowing I'm putting in quality oil in my truck! Oil is the lifeblood of your Truck. Take care of it
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great oil !!
    By  CRAIG,  a  Verified Buyer  on  March 27, 2023
    Love this oil motor runs smooth. Amsoil is a great product.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great product been using it for awhile now
    By  JARRED,  a  Verified Buyer  on  March 16, 2023
    Great product been using it for awhile now!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    4x 5-40 diesel oil
    By  DUANE,  a  Verified Buyer  from  lakewood ca   on  February 15, 2023
    amsoil is all in use in everything i drive
    Bottom Line
    No, I would not recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great product
    By  Eric,  a  Verified Buyer  from  MT  on  January 03, 2023
    Great product. Takes the smoke out of the back end and makes cold starts effortless.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great oil
    By  JIM,  a  Verified Buyer  from  Arizona  on  December 31, 2022
    I used this oil for my first oil change (2022 F-350 Diesel). The engine starts and runs quieter than with the factory fill.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best oil
    By  MATT,  a  Verified Buyer  on  December 31, 2022
    Love this stuff
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    The good stuff
    By  DAN,  a  Verified Buyer  from  Massachusetts   on  December 25, 2022
    Used to run rotella t6 but switched to this stuff ever since I discovered the preferred customer program and will never go back! Run it in my powerstroke and my tractor now as well
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?