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

Product code : DEO1G-CA

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 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



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

  • 5
    Buy it Use it
    By  STEVE,  a  Verified Buyer  from  Little Rock ,AR  on  March 02, 2021

    Describe the issue

    I run this in my 97 Dodge 12 valve Cummins 190K and it runs smooth as silk , hauled a 33'camper from Little Rock to Grand Junction ,CO Feb 2020 and it purred right through the Rockies zero problems . I suggest it to everyone I can .
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  TODD,  a  Verified Buyer  on  March 02, 2021

    Describe the issue

    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  MATHEW,  a  Verified Buyer  from  Bloomington, MN  on  March 02, 2021

    Describe the issue

    Great oil for all weather applications
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Best Oil
    By  LEROY,  a  Verified Buyer  from  Florida  on  February 26, 2021

    Describe the issue

    Reviewed the test results and I am satisfied the oil suits my needs. I do some heavy hauling and have used the oil since the truck was new. No issues.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Diesel oil
    By  RYAN,  a  Verified Buyer  from  Florida   on  February 25, 2021

    Describe the issue

    Love amsoil the only oil I run in my diesel truck
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  TODD,  a  Verified Buyer  on  February 24, 2021

    Describe the issue

    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  ADAM,  a  Verified Buyer  on  February 23, 2021

    Describe the issue

    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Difference you can here
    By  STEPHEN,  a  Verified Buyer  on  February 23, 2021

    Describe the issue

    I was running another big name brand (T6) synthetic oil before, after switching to AMS oil I can here a difference in how the motor idles. Much smoother and quieter than before
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Best oil
    By  ALEC,  a  Verified Buyer  from  LA County   on  February 23, 2021

    Describe the issue

    Not much to say other then best oil on the market. I don’t use anything else. I use this in my 2001 Chevy Duramax that is always towing. 10/10 recommend
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    GREAT PRODUCT / CUSTOMER SERVICE
    By  JAMES,  a  Verified Buyer  from  NORTH CAROLINA  on  February 21, 2021

    Describe the issue

    GREAT PRODUCT BEEN USING FOR YEARS WITH NO ISSUES, CUSTOMER SERVICE ALSO RECEPTIVE TO REQUESTS. I FEEL LIKE I KNOW THEM PERSONALLY
    Bottom Line
    Yes, I would recommend this to a friend.