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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

Data Bulletin

Warranty

SDS



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

  • 5 star rating
    The best
    By  MARK,  a  Verified Buyer  on  March 25, 2023
    I have been running this oil since I bought the truck new. I only trust Amsoil in my truck.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Amsoil 15w-40
    By  ANDREW,  a  Verified Buyer  on  March 22, 2023
    Been using Amsoil’s 15w-40 on my Duramax for years and I absolutely love it. I can get 15-18k intervals out of it and it’s still got a couple thousand more miles left in it. Take care of your vehicle and it’ll take care of you… run amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great product
    By  MARK,  a  Verified Buyer  from  Washington State  on  March 21, 2023
    Great product with super fast shipping! If you have a tech question they are quick to respond to your email.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Superior products
    By  RON,  a  Verified Buyer  from  Colorado  on  March 21, 2023
    Have used Amsoil Diesel Oil in My 2005 F250 for 190,000 miles i would not use any thing else.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great product
    By  ADAM,  a  Verified Buyer  from  Texas  on  March 20, 2023
    This is the first time I have used the signature series oil I always used the silver jug previously. I rate this oil so highly due to the instant noticeable increase in fuel economy after my most recent oil change. The big diesel runs at lower RPMs during all driving ranges and I have gained approximately 2mpg!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best
    By  JORDAN,  a  Verified Buyer  on  March 18, 2023
    Love it
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Amsoil products
    By  Steve,  a  Verified Buyer  from  Illinois  on  March 13, 2023
    I've been using Amsoil in my 6.0 Powerstroke for almost two decades now highest quality oils available that's why I use it and that's why I recommend it
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Diesel oil
    By  LEAU,  a  Verified Buyer  from  Louisiana   on  March 10, 2023
    Great product have been using it for several years
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best by far
    By  GREG,  a  Verified Buyer  from  Pulaski va  on  March 08, 2023
    Best oil I have ever had!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Good product.
    By  JOHAN,  a  Verified Buyer  from  Nebraska   on  March 07, 2023
    I have been using this oil in my long distance trucks for years. Cummins and Caterpillars Oil performance is what i hold in high regard and this has never disappointed me.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?