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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
    Been using it for years
    By  ROGER,  a  Verified Buyer  on  November 30, 2021

    Describe the issue

    I've been using this in my '06 Dodge diesel for years at extended change intervals. I also use it in a small diesel tractor. It gives me easier cold weather starts than 15-40. I don't see any reason not to continue to do so. I run Amsoil in two generators, two motorcycles (Harley Davidson 20-50 and KTM 15-50) and run the Saber oil in my trimmers. No complaints.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Great oil
    By  JAMES,  a  Verified Buyer  from  Illinois   on  November 29, 2021

    Describe the issue

    Been running this oil in my 7.3 powerstroke for 200k and truck has 300k on it now. I usually ran the oil for about a total of 10k miles with 1 filter change at 5k miles, but recently I decided to have my oil tested and with changing just my oil filters every 5-6 miles. I ran the same oil for over 18k miles and it still checked out good. I do hotshot so I put on miles fast and I won't use any other oil brands.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Amsoil
    By  GREG,  a  Verified Buyer  from  Agoura,Calif.  on  November 29, 2021

    Describe the issue

    Happy with your products. Ships quickly. Easy to use website.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Used it in my diesel Van
    By  KURT,  a  Verified Buyer  from  Las Vegas NV  on  November 29, 2021

    Describe the issue

    Used Amsoil in my 2006 Ford Van. runs much smoother and much quieter now than previous oil that has been used. Seems to have more pick -up that before!!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Awesome product/ Synthetic oil
    By  Nick,  a  Verified Buyer  from  SoCal  on  November 23, 2021

    Describe the issue

    Absolutely appreciate this oil product for my 7.3 diesel and the truck loves it too will continue to purchase.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Diesel
    By  MICHAEL,  a  Verified Buyer  from  Wy  on  November 22, 2021

    Describe the issue

    Absolutely love this in my Duramax runs better gets good fuel mileage
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    jAG
    By  JOSE A,  a  Verified Buyer  from  Gypsum co  on  November 19, 2021

    Describe the issue

    Great product use amsoil in all my vehicles and snowmobiles should say all my toys
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Best diesel oil 9n the market
    By  Steven,  a  Verified Buyer  from  Wisconsin  on  November 15, 2021

    Describe the issue

    My truck use to go throw 2 qts of oil running rotela 5w40 in 5000 miles. Switched to ams oil and now I can go 10000 miles no oil lost. I am very happy.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Max duty synthetic Diesel oil 5w-40
    By  BERNIE,  a  Verified Buyer  on  November 15, 2021

    Describe the issue

    Great product! Will continue using!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    The best
    By  GARY,  a  Verified Buyer  from  Hampton Virginia   on  November 13, 2021

    Describe the issue

    Gives me all the protection I need in my Duramax. Gives me better fuel mileage then Rotella
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?