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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
    Diesel oil
    By  THOMAS,  a  Verified Buyer  on  July 04, 2024
    Great oil. Holds up well. Seems to keep everything running smooth. 160,000mi and no issues so far
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil !
    By  KYLE,  a  Verified Buyer  from  Barrie  on  July 02, 2024
    Great oil even under extreme heat my oil pressure is still good 👍🏼
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Tuff
    By  STAN,  a  Verified Buyer  from  Florida  on  July 02, 2024
    Amazing, bought this for my military house generator and i am glad I did! Great oil and products!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    My Cummings diesel is very important to me
    By  RANDY,  a  Verified Buyer  from  Catonsville, MD  on  June 29, 2024
    I have been driving my Cummings powered Dodge since 2013 and protect my engine with the best synthetic oil I can. AMSOIL is my choice.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Diesel oil
    By  DAVID,  a  Verified Buyer  from  Saluda, South Carolina   on  June 27, 2024
    I use this oil in my 86 Chevrolet G30 Highcube van with a 6.2 non-turbo engine and the oil pressure increased about 5 psi and oil consumption on long trips decreased. Also the oil drips have decreased, cutting down on floor clean up.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 3 star rating
    Diesel oil
    By  Larry,  a  Verified Buyer  from  MT  on  June 25, 2024
    I can not give a review on any oil with very few miles on the vehicle I'm using it in. Get back to me in about !00,000 miles or about 6 or 7 years.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Awesome oil
    By  TANNER,  a  Verified Buyer  on  June 24, 2024
    High quality oil at an affordable price, definitely recommend to my friends and family. Preferred customer program is awesome too!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Diesel oil
    By  CHRISTOPHER,  a  Verified Buyer  from  Oregon   on  June 23, 2024
    This oil works great and I like getting it delivered
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Longevity
    By  RON,  a  Verified Buyer  from  SoCal  on  June 23, 2024
    The oil more than meets expectations and being rated for 25k miles or 1 year is amazing on its own! Being that I drive this vehicle less than 6,000 miles a year, I guess I will be doing the annual oil change! So far, the motor seems to idle and run smoother and not stay in the high pressure state as long! I will definitely buy this again!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Awesomeness
    By  RICK,  a  Verified Buyer  from  Belle River  on  June 20, 2024
    I’m an 100% AMSOIL user I would not use anything but from my lawnmower to all vehicles and farm equipment
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?