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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
    Quality product
    By  JEFF,  a  Verified Buyer  on  January 22, 2022

    Describe the issue

    Excellent product.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Signature Series Max Duty Diesel Oil 15w-40
    By  BILL,  a  Verified Buyer  from  Canada  on  January 18, 2022

    Describe the issue

    I have a 5.9 cummins ram with a fully built compound turbo set-up and Goerend transmission. The truck makes 800+ HP at the wheels and I drive it quite hard. I have only used and will only use Amsoil products for this build. I am 63 and and have seen and used different products over the decades. It is so nice to now just look at the Amsoil website and order what I need for whatever I am working on. I have always told my sons "oil is cheap, engines are expensive"
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    15W-40 oil
    By  LEONARD,  a  Verified Buyer  on  January 17, 2022

    Describe the issue

    This oil works great and protects my engine. It was easy to order and arrived quickly. Thanks
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Amazing oil
    By  HUSSAIN,  a  Verified Buyer  from  Burleson tx  on  January 16, 2022

    Describe the issue

    I ordered this oil because i saw very good amazing reviews and honestly its one of the best oils I've used in my truck gives great protection and great milage
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Happy long time customer
    By  BRUCE,  a  Verified Buyer  on  January 15, 2022

    Describe the issue

    I've been very happy with the customer service with Amsoil for a long time. Easy ordering, very fast shipping. I use their products in all my vehicles. I also use their products in my offshore boat.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Great 👍
    By  Goose,  a  Verified Buyer  from  British Columbia   on  January 15, 2022

    Describe the issue

    I started using amsoil 3 years ago after lots of research and found it to be the best. I use it for everything on my pickup.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 4
    Greatr
    By  DON,  a  Verified Buyer  from  Iowa  on  January 14, 2022

    Describe the issue

    I've run Amsoil in my 6.6 Duramax in screaming hot and sub zero temps with no issues at all. I intend to continue to use it.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Good oil
    By  JARED,  a  Verified Buyer  on  January 13, 2022

    Describe the issue

    Its a good oil but i was surprised i didnt get any stickers. When i bought it previously i got stickers
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Very fast shipping
    By  Chad,  a  Verified Buyer  from  Utah  on  January 12, 2022

    Describe the issue

    Awesome shipping time!!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Great Product
    By  BRETT,  a  Verified Buyer  from  Cocoa,FL.  on  January 10, 2022

    Describe the issue

    I have used AMSOIL in my Ford diesel for 15 plus years and still going strong at over 444k miles!
    Was this review helpful?