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AMSOIL Signature Series 5W-40 100% Synthetic Max-Duty Diesel Oil

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
  • Confidently extend drain intervals

     

    1Based on third-party testing in the Detroit Diesel DD13 Scuffing Test for specification DFS 93K222 using 5W-30 as worst-case representation

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AMSOIL Signature Series 5W-40 100% Synthetic Max-Duty Diesel Oil



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.

AMSOIL Signature Series 5W-40 100% Synthetic Max-Duty Diesel Oil

Data Bulletin

Warranty

SDS



AMSOIL Signature Series 5W-40 100% Synthetic Max-Duty Diesel Oil

  • 5 star rating
    Return
    By  ALLEN,  a  Verified Buyer  from  512 s main st Shrewsbury pa 17361  on  May 14, 2024
    Third time I connected you. You were supposed to send me a self address ticket to send back a gallon I ordered to much. I’m giving up. But it’s 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
    Quality oil
    By  WAYNE,  a  Verified Buyer  on  May 13, 2024
    Best oil for duramax engines
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Best there is...
    By  ROD,  a  Verified Buyer  from  Southwest FL   on  May 12, 2024
    Only oil I have ever used for my trucks.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    2006 Duramax
    By  RAY,  a  Verified Buyer  on  May 11, 2024
    I used the in my 2006 Duramax since it was new! I have 500,000 KLMs on it now and never had any issues with this engine!!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    diesel oil
    By  DAVID,  a  Verified Buyer  from  chicago  on  May 10, 2024
    the best oil you can buy.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great oil super price
    By  TONY,  a  Verified Buyer  on  May 05, 2024
    Love this oil. 6.7 power stroke with 95,000 miles It’s the only oil that’s been used since new
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Max duty oil
    By  Scott,  a  Verified Buyer  from  AZ  on  May 01, 2024
    This is the best oil that you can get. You can see how well it's held up during oil changes. It's the only thing I'll ever use in my super duty.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Bad reward good oil
    By  ADAM,  a  Verified Buyer  from  Utah  on  April 29, 2024
    I exclusively use Amsoil on all my vehicles and toys. The only negative I have is with the rewards. Why aren’t they just built in? I always get an email saying free this or free that but never remember what the code is. Why not just include it?
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Product
    By  JASON,  a  Verified Buyer  from  Indianapolis  on  April 29, 2024
    Using it on my 2015 Ram Ecodiesel, It immediately quieted and smoothed out the engine. I'm at 125k miles and no issues. I will continue to send in my oil evaluations for testing and hope to see this truck live a long and happy life. Looking to do my transmission next to prolong longevity and performance. Thank you Amsoil for a great product and for making kits specific to my vehicle, it takes the guess work out of it. Thank you,
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The best
    By  HAROLD,  a  Verified Buyer  from  New Albany Indiana   on  April 27, 2024
    I was driving over 4000 miles a week and only used Amsoil. The only oil that would hold up.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?