Back

Close Icon

Main Menu

Your order may take longer than normal to arrive. We are experiencing extremely high demand and freight carriers are experiencing delays nationwide.

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
    Great product
    By  JIM,  a  Verified Buyer  from  Jacksonville, Fl  on  July 23, 2021

    Describe the issue

    Great product, no issues.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    The ONLY oil I use!
    By  JUSTIN,  a  Verified Buyer  from  Forney TX  on  July 22, 2021

    Describe the issue

    I have a 2008 LMM and used to use T6 (if you are looking at this oil, you should know what that is) cause my grandfather used it in his diesels. Found this, started using it. Everything noticeably smoother. Quick delivery and got a good discount program. Oh, and I get stickers too. Haha
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Reliable and quick delivery
    By  ROBERT,  a  Verified Buyer  from  80134  on  July 12, 2021

    Describe the issue

    Been using Amsoil for many years knowing the performance of their many products, I will continue to be a loyal customer.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Duramax
    By  DENNIS,  a  Verified Buyer  from  Indiana   on  July 11, 2021

    Describe the issue

    Love this for my duramax.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Good quality
    By  RONNIE,  a  Verified Buyer  on  July 10, 2021

    Describe the issue

    I’m Very happy with this product. My truck is happy too 6.7 cummins
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Best oil
    By  PIERRE,  a  Verified Buyer  from  Ontario   on  July 07, 2021

    Describe the issue

    Been using this oil for over 30 years.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Diesel oil
    By  JOHN,  a  Verified Buyer  from  Panama City   on  July 06, 2021

    Describe the issue

    In my opinion this is a good oil to run in a Cummins Diesel engine good cleaning properties
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Diesel review
    By  ROBBIE,  a  Verified Buyer  on  July 05, 2021

    Describe the issue

    Great service and fast delivery and my truck runs much better on Amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Heavy duty engine oil
    By  OLIVER,  a  Verified Buyer  from  Windsor  on  July 05, 2021

    Describe the issue

    Best engine oil ever. Keep the motor clean . Clean means also long life for the engine
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Best of the best
    By  KEVIN,  a  Verified Buyer  from  Grain Valley Mo.  on  July 05, 2021

    Describe the issue

    I use all of Amzoil products in every thing I own, I just had the oil changed in my truck by the dealership because I have to do to warranty contract, drove for a week and changed it with my Amzoil, noticeably quieter (Deisel). I paid almost 80 grand for the truck I want the best oil for it.
    Bottom Line
    Yes, I would recommend this to a friend.