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

Product code : DEOQT-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 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
    Great product
    By  MIKE,  a  Verified Buyer  on  October 20, 2021

    Describe the issue

    Amsoil always arrives in a timely fashion and my engine loves it. Would recommend this oil to anybody who wants the best for their diesel.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Best oil in the market
    By  CHRIS,  a  Verified Buyer  on  October 20, 2021

    Describe the issue

    I run AMSOIL in my new Cummins and it’s amazing. I had my oil tested by an independent lab and it is better than any other oil on the planet!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Amsoil 15w40 diesel oil
    By  RONNALLE,  a  Verified Buyer  from  Parker  on  October 15, 2021

    Describe the issue

    Up to 25000 miles for next oil change. With amsoil oil filter and product. Recommend oil sample's during long drain interval.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Excellent
    By  MATTHEW,  a  Verified Buyer  from  New Jersey   on  October 13, 2021

    Describe the issue

    Excellent product, first time running AMS oil I noticed my diesel run smoother immediately.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    oil change
    By  LUIS,  a  Verified Buyer  from  port barrington  on  October 12, 2021

    Describe the issue

    great oil love it
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Runs like new
    By  SAMUEL,  a  Verified Buyer  from  Nyc  on  October 09, 2021

    Describe the issue

    Keeps my trailblazer Ss running strong
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Awesome Product
    By  act,  a  Verified Buyer  from  Maplesville  on  October 08, 2021

    Describe the issue

    I will not use anything else, Works great, Highly Recommend
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Oil
    By  STEVE,  a  Verified Buyer  from  Michigan   on  October 08, 2021

    Describe the issue

    I love this product has not let me down
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Awesomeness
    By  ASA,  a  Verified Buyer  on  October 08, 2021

    Describe the issue

    Always makes my Truck run like new every time I change the oil. That’s not an overstatement either, I’ve used royal purple for years and then I decided to switch over due to all my buddies who I know run Amsoil. Best that money can buy
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Great Product
    By  Ray,  a  Verified Buyer  from  Nebraska   on  October 04, 2021

    Describe the issue

    Shipping was quick. Great buy. Comparable to what’s at your local stores. I have both engine oil and differential oil in my truck. Love them both.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?