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Signature Series Max-Duty Synthetic Diesel Oil 5W-40

Product code : DEOQTC-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

  • 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

Signature Series Max-Duty Synthetic Diesel Oil 5W-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 5W-40

Data Bulletin

Warranty

SDS



Signature Series Max-Duty Synthetic Diesel Oil 5W-40

  • 5 star rating
    Great oil for my Cummins
    By  KENNETH,  a  Verified Buyer  on  September 12, 2023
    Switched over from Royal Purple and could not be happier.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great diesel oil
    By  DANO,  a  Verified Buyer  on  September 11, 2023
    All usual Amsoil doesn't disappoint. Great oil for Ram 6.7, and there deliveries rapid. Will always buy my oils from Amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Good stuff
    By  RONNIE,  a  Verified Buyer  on  September 08, 2023
    Worth the money
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Long lasting
    By  LUCY,  a  Verified Buyer  from  Killeen, Texas  on  September 08, 2023
    Quality stuff here. Long lasting good quality oil. A bit pricey but you get what you pay for
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Diesel Oil 5W-40
    By  RICK,  a  Verified Buyer  from  MA  on  September 06, 2023
    Use Amsoil Signature Series Max-Duty Synthetic Diesel Oil 5W-40 for every oil change. Rated the best for Cummins diesels.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Backup for m 3 diesels
    By  Steven,  a  Verified Buyer  from  California  on  September 03, 2023
    This is just outstanding oil.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Car
    By  ROBERT,  a  Verified Buyer  from  Fairview   on  September 03, 2023
    Car seems to run more smoothly
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Ram 2500 diesel
    By  MARK,  a  Verified Buyer  from  Austin, Texas   on  September 01, 2023
    Good stuff!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Just buy it
    By  MIKE,  a  Verified Buyer  on  August 30, 2023
    Surprised, a lot smother and quitter engine
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Using this oil for many years
    By  MAHRAD,  a  Verified Buyer  from  Central Florida  on  August 27, 2023
    I have been using the 15 W 40 Amsoil diesel oil for many years on different GMC Duramax diesels. All on lower mileage trucks. It is a good durable oil. No burning of loss of oil. No engine mechanical issues. I perform the oil changes myself. Libricity of the old oil is very good. The 2.5 gallon container is difficult to handle without spilling. I recommend getting it in quart size containers. I recommend the oil.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?