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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 star rating
    My experience with Amsoil
    By  LAYTON,  a  Verified Buyer  from  Fort Pierce   on  May 21, 2022
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    I owned a auto repair shop for 45 years Have used there products in my vehicle Never had anything oil related problems Great product.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Oil change
    By  ANTHONY,  a  Verified Buyer  on  May 20, 2022
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    I switched using my conventional oil to Amsoil in my duramax. The only reason I gave it a 4 was I need to see the results when I do a filter change. If it looks good then I will buy the oil bypass system to get cleaner oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    oil
    By  TOM,  a  Verified Buyer  on  May 11, 2022
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    the only oil I use in my truck
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Second to none!
    By  DANE,  a  Verified Buyer  on  May 11, 2022
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    The max duty product is second to none. Use with confidence. If you’re looking for a 5w-30/40 synthetic oil and truly want the best (actual synthetic blend) on the market that’s available to order and will arrive at your door fast…look no further.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    AMSOIL Full Synthetic Diesel Motor Oil
    By  MAX,  a  Verified Buyer  on  May 10, 2022
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    I highly recommend this motor oil for all your diesel trucks.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Quieten that engine
    By  BILLY,  a  Verified Buyer  from  Va  on  May 10, 2022
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    This is the second time if used thin in my 2019 John Deere 2025r. It definitely makes the engine quieter and noticed a little smoother as well!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Sweet Oil
    By  THOMAS,  a  Verified Buyer  from  Iowa  on  May 07, 2022
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    With the current inflation ridden prices on Diesel oil, Amsoil is no longer high priced. Signature series is great Oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Signature 15w40 diesel oil
    By  ED,  a  Verified Buyer  on  May 06, 2022
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    Always performs well reduced engine temperatures when towing with my truck dodge 2500 Cummins diesel also my sons 6.7 ford while towing keeps temperatures down, I have been a dealer as well as a preferred customer 13 years Using Amsoil and still going strong Motorcoach, tractors and small engines
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent product
    By  JACKIE,  a  Verified Buyer  from  Maryland   on  May 06, 2022
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    Excellent product and quick delivery
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  CHRIS,  a  Verified Buyer  from  Oklahoma  on  May 06, 2022
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    Great oil.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?