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

Product code : DEOTP-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 diesel oil
    By  ALFREDO,  a  Verified Buyer  on  April 12, 2021

    Describe the issue

    Overall great oil
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    best stuff in the market
    By  RONNIE,  a  Verified Buyer  from  lake Anna   on  April 12, 2021

    Describe the issue

    best stuff on the market use it in my truck and both my Harleys
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Go to in Ford 6.7 powerstroke
    By  CHRIS,  a  Verified Buyer  from  new Hampshire  on  April 11, 2021

    Describe the issue

    When you ante up $10K for the industries most powerful diesel you want to take steps to ensure it is well kept. Have been using thee Signature Oil with the Amsoil by-pass system. Have been happy with the results. Highly recommended.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Quiten that Diesel down!
    By  Billy,  a  Verified Buyer  from  Virginia  on  April 11, 2021

    Describe the issue

    So, it was time to change the oil in my John Deere 2025r. Being a Amsoil PC I decided to try Amsoil in my tractor. I used Amsoil Engine Flush before pulling the plug and after draining my oil I'm glad I did! My oil was full of soot and carbon! After installing my Amsoil filter ( got the filter recommendation from Amsoil Tech.) I added some fresh Amsoil 5w-40 and started my JD up. I've never heard it run so quite! Almost sounded like a gas engine it was so quite! Looking forward to seeing if I can ' feel the protection' when I use it !! Thanks Amsoil!
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Best oil by far
    By  OLIVER,  a  Verified Buyer  from  Canada  on  April 11, 2021

    Describe the issue

    I used this oil for years in my truck and my cars. Best oil by any circumstances
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Diesel oil
    By  ROBERT,  a  Verified Buyer  from  Brandon vermont  on  April 11, 2021

    Describe the issue

    I have been using this oil the truck has over 200 thousand miles and going strong I change it once a year and I also a change the filter at 6 months intervals
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Great oil
    By  FRED,  a  Verified Buyer  from  Arizona  on  April 10, 2021

    Describe the issue

    Love this oil for my Duramax diesel. Just made a 3,000 mile trip and didn’t have to add any. Love the wide mouth of the quart container as it pours really fast
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Diesel Oil
    By  JANEEN,  a  Verified Buyer  from  Oregon  on  April 09, 2021

    Describe the issue

    Superior product.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Awesome oil.
    By  Stephen,  a  Verified Buyer  from  Florida  on  April 08, 2021

    Describe the issue

    I refuse to use any other oils in any of my vehicles. Truck bike boat tractor even lawnmower.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Great oil
    By  JAMES,  a  Verified Buyer  on  April 05, 2021

    Describe the issue

    I run this in my 7.3 powerstroke for 10k miles and change the oil filter halfway. So far no issues after 130k
    Bottom Line
    Yes, I would recommend this to a friend.