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AMSOIL Signature Series 15W-40 100% Synthetic Max-Duty Diesel Oil

Product code : DMEQT-EA

  • Outstanding extreme-pressure protection
  • Delivers 6X more wear protection1
  • Maintains proper viscosity (thickness)
  • Minimizes oil consumption
  • Maximizes fuel efficiency
  • Excels in extreme temperatures
  • Confidently extend drain intervals

     

    1Based on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 5W-30 as worst-case representation

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AMSOIL Signature Series 15W-40 100% Synthetic Max-Duty Diesel Oil



Developed to protect the horsepower diesel enthusiasts crave and extend the life of hard-working commercial equipment in the most severe conditions. Signature Series synthetic technology delivers max-duty protection in on- and off-road applications.

See the Product Data Bulletin for full details.

MAXIMUM ENGINE PROTECTION

  • Delivers 6X more wear protection,1 delivering extra protection so you can push your diesel with peace of mind
  • Provides long-lasting wear protection, keeping cylinder liners looking like new2
  • Delivers up to 60 percent better turbo cleanliness3
  • Withstands the extra demands you place on the turbo when pulling heavy loads or updating the tune for maximum horsepower
  • Provides up to 2X better rust protection4

1Based on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 5W-30 as worst-case representation
2Based on independent testing of AMSOIL 5W-30 Signature Series Max-Duty Synthetic Diesel Oil and a leading conventional 15W-40 diesel oil using the Detroit Diesel* DD13 Scuffing test for specification DFS 93K222.
3Based on specification standards of CAT C13 2nd Ring Top Land Carbon testing
4Based on industry standard testing using the NMMA FC-W Rust Test.


Delivers More Wear Protection

Third-party testing shows Signature Series Max-Duty Synthetic Diesel Oil delivers 6X more protection against wear than required by Detroit Diesel’s* standard.II

IIBased on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 5W-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.


AMSOIL Fights Wear

AMSOIL delivers powerful engine protection. How good is it? In third-party testing compared to a leading brand, AMSOIL provided long-lasting wear protection, keeping cylinder liners looking like new.DD

AMSOIL Fights Wear – AMSOIL delivers powerful engine protection. How good is it? In third-party testing compared to a leading brand, AMSOIL provided long-lasting wear protection, keeping cylinder liners looking like new.

DDBased on third-party testing of AMSOIL 5W-30 Signature Series Max-Duty Synthetic Diesel Oil and a leading conventional 15W-40 diesel oil using the Detroit Diesel* DD13 Scuffing test for specification DFS 93K222.
*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.


Keeps Turbos Clean

AMSOIL Signature Series Max-Duty Synthetic Diesel Oil provides protection boosted to the max, delivering up to 60% better turbo cleanlinessJ and withstanding the extra demands you place on the turbo when pulling heavy loads or updating the tune for maximum horsepower.

JBased on specification standards of CAT C13 2nd Ring Top Land Carbon testing


Protects Against Rust

Provides up to 2X better rust protection.K Protects Against Rust – Provides up to 2X better rust protection.

KBased on industry standard testing using the NMMA FC-W Rust Test.


VISCOSITY CONTROL

  • Resists oxidation and the thickening effects of soot contamination
  • Retains viscosity after high-temperature service for maximum engine protection and efficiency
  • Provides up to 76 percent less oil consumption5

5Than required by the API CK-4 standard in the Caterpillar-1N oil consumption test


Reduces Oil Consumption

Signature Series Max-Duty Synthetic Diesel Oil provides up to 76% less oil consumption.L

Reduces Oil Consumption – Signature Series Max-Duty Synthetic Diesel Oil provides up to 76% less oil consumption.

LThan 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
  • Resists thermal (heat) breakdown better than conventional and competing synthetic diesel oils.
  • Stays fluid in sub-zero temperatures for easier starting, improved oil flow and reduced wear.

See the Product Data Bulletin for full details.

AMSOIL Signature Series 15W-40 100% Synthetic Max-Duty Diesel Oil

Data Bulletin

Warranty

SDS



AMSOIL Signature Series 15W-40 100% Synthetic Max-Duty Diesel Oil

  • 5 star rating
    best on the market
    By  RODNEY,  a  Verified Buyer  on  February 21, 2024
    this is the best oil on the market
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Superior products
    By  RONALD,  a  Verified Buyer  from  Phippsburg, Colorado  on  February 19, 2024
    I have used Amsoil 5w/40 in my diesel F250 since 2008 I would not use anything else!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    number 1 oil
    By  luis,  a  Verified Buyer  from  FL  on  February 06, 2024
    great product
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Works great!
    By  JOSHUA,  a  Verified Buyer  from  Auburn Indiana   on  February 03, 2024
    Best quality oil on the market!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Product recommendations
    By  STEVEN,  a  Verified Buyer  from  Sequim  on  February 03, 2024
    Great product, price is worth the extended life and frequent changes.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Excellent
    By  PHIL,  a  Verified Buyer  on  February 03, 2024
    I run this oil in my 2022 Duramax. This oil does not feel like it broke down at all after the 1 year change interval. I rubbed a little of the old oil between my fingers after the change, and it still felt new. I’ll keeping running it in my truck for years to come.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Converting Dodge Ram 2500 to Amsoil 100% Synthetic
    By  CHARLIE,  a  Verified Buyer  from  CA  on  January 30, 2024
    Just changed oil in my 2017 Dodge Ram 2500 to Amsoil 15W-40 100% Synthetic and what a difference in performance. Definitely my truck is a lot quieter and seems to have more torque. Getting ready to change my 2015 Lexus RX 350 to Amsoil 100% synthetic, these Amsoil products have really made a difference in the performance of my vehicles. A+
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil protects@
    By  Seventrumpets42 ,  a  Verified Buyer  from  Colorado   on  January 22, 2024
    I have only used Amsoil Signature 5-40 Diesel oil in my 2016 Ram since I purchased it with 722 miles. I do routine oil analysis at Blackstone Labs. I follow manufacturers recommended oil change interval of 10k. I just completed the 170k change and await the lab's analysis. I usually add 1/2 qt. between changes. Amsoil makes quality lubricants that can be surpassed!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great as always
    By  RICK,  a  Verified Buyer  on  January 21, 2024
    Shipped promptly, and is a great product. Unpaid spokes person.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best diesel oil
    By  kingsley,  a  Verified Buyer  from  AZ  on  January 15, 2024
    This is the best diesel oil to use in your diesel engine....my cummins works & sounds smoother
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?