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Signature Series Max-Duty Synthetic Diesel Oil 15W-40

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

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

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

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

Signature Series Max-Duty Synthetic Diesel Oil 15W-40



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.

Signature Series Max-Duty Synthetic Diesel Oil 15W-40



Signature Series Max-Duty Synthetic Diesel Oil 15W-40

  • 5
    This is the only product I will run in my truck
    By  SEAN,  a  Verified Buyer  from  In exercise owner  on  June 17, 2021

    Describe the issue

    Gray products have no problems
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Good product great packaging.
    By  BRUCE,  a  Verified Buyer  on  June 16, 2021

    Describe the issue

    All AMS are quality products.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Syn Oil
    By  RONALD,  a  Verified Buyer  from  Oregon  on  June 12, 2021

    Describe the issue

    Been using for years and this is the best
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Really good, I’m happy how the engine is working now
    By  LUIS,  a  Verified Buyer  from  Homestead FL  on  June 11, 2021

    Describe the issue

    I’m happy to use amsoil synthetic oil for my pickup truck,the engine sounds a lat better than before
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Great oil!
    By  RANDAL,  a  Verified Buyer  on  June 09, 2021

    Describe the issue

    This oil is impressive!
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Good stuff!
    By  NEHEMIAH,  a  Verified Buyer  from  Indiana   on  June 08, 2021

    Describe the issue

    Great product and even better customer service and shipping. All my vehicles get Amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Signature series
    By  COLIN,  a  Verified Buyer  on  June 07, 2021

    Describe the issue

    Used this product for the last 5 oil changes and many more to come.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Great Product
    By  MICHAEL,  a  Verified Buyer  from  Farmington, CA  on  June 06, 2021

    Describe the issue

    I love Amsoil products. It gives me great comfort and piece of mind knowing all of my engines from my Can Am side by side, my lawn mowers, motorcycle and all my trucks are protected with the best oils on the market today.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Duramax
    By  Anthony,  a  Verified Buyer  from  MN  on  June 04, 2021

    Describe the issue

    Great oil for any truck
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    An outstanding CK4 oil
    By  ofelas,  a  Verified Buyer  on  June 04, 2021

    Describe the issue

    Amsoil's excellent SS oils are the only CK4 lubes I'll use on a CI4+ application, especially if I don't have immediate access to AME/HDD.
    Bottom Line
    Yes, I would recommend this to a friend.