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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
    By  JESSE,  a  Verified Buyer  from  Ratcliff Ar  on  January 24, 2021

    Describe the issue

    Great oil. Instant oil pressure on star up in cold weather.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  ROBERT,  a  Verified Buyer  on  January 24, 2021

    Describe the issue

    So far awesome product
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  MIKE,  a  Verified Buyer  from  Dodgeville Wisconsin   on  January 22, 2021

    Describe the issue

    The top 2 best, most honest mechanics I know recommend Amsoil. I've been using it for a couple years now and agree it's the best. Most noticeable to me is starting my diesel in the winter has improved as I don't have to plug it in anymore and it warms up faster. Also like not having to change the oil as often. Worth the money. Mike
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  RICKY,  a  Verified Buyer  on  January 21, 2021

    Describe the issue

    This is very good oil for my 6.7 diesel. This is the best oil I have used in any of my diesel trucks.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  MATTHEW,  a  Verified Buyer  on  January 21, 2021

    Describe the issue

    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    2.5 Gallon size
    By  SCOTT,  a  Verified Buyer  on  January 20, 2021

    Describe the issue

    I didn't realize there was such a size until I browsed the Amsoil site. I run the PPE filter on my Duramax so a big jug and small jug does the job with no leftovers. So convenient to get order sent to my home.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Only oil for my trucks
    By  ANDREW,  a  Verified Buyer  on  January 19, 2021

    Describe the issue

    Love this oil, I have been using it for years
    Bottom Line
    Yes, I would recommend this to a friend.
  • 4
    Satisfied as Usual with Amsoil
    By  SCOTT,  a  Verified Buyer  from  Mississippi  on  January 19, 2021

    Describe the issue

    Quick delivery for a superior product, use Amsoil in all my vehicles
    Bottom Line
    Yes, I would recommend this to a friend.
  • 4
    By  ALBERT,  a  Verified Buyer  from  Cold Lake, Alberta, Canada  on  January 19, 2021

    Describe the issue

    I did find that this lubricant worked on reverse in saying it will increase fuel mileage, my with backwards. I still continue using this oil for my 2015 GMC 3500 HD Diesel engine
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    best oil
    By  RODNEY,  a  Verified Buyer  on  January 19, 2021

    Describe the issue

    best oil fastest service
    Bottom Line
    Yes, I would recommend this to a friend.