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Signature Series Max-Duty Synthetic Diesel Oil 15W-40

Product code : DMEQT-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 15W-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 15W-40



Signature Series Max-Duty Synthetic Diesel Oil 15W-40

  • 5 star rating
    Great oil will continue to buy
    By  JOSH,  a  Verified Buyer  from  Farrwest  on  September 26, 2022
    Your oil is better then others that I’ve used so I will continue to use
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Reliable Products
    By  JESSIE,  a  Verified Buyer  on  September 25, 2022
    AMSOIL has been a part of my engine maintenance regimen for many, many years and has always out performed the competition.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Diesel oil
    By  MARTIN,  a  Verified Buyer  on  September 25, 2022
    Great so far!!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Diesel oil
    By  NICK,  a  Verified Buyer  on  September 21, 2022
    Quick delivery can’t beat Amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Synthetic Diesel Oil
    By  ALBERT,  a  Verified Buyer  from  Cold Lake, AB  on  September 21, 2022
    By using this type of engine oil I found that my engine runs cooler, Fuel efficiency has also changed. Engine itself being diesel with this oil the motor runs quieter.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    For my 2019 F250
    By  PAUL,  a  Verified Buyer  from  Flowery Branch, Ga  on  September 13, 2022
    I tow approx 10k lbs pretty consistently (40-50% of my miles) and have always used Amsoil for the extended drain interval. With about 40k mi on my truck and approx 15k miles on my oil, I decided to send my oil to blackstone for analysis. I’ll spare you all of the details but will tell you that they noted that I could safely extend my oil change interval out approx 10k more miles, taking the oil life to 25k miles. While they may be true, I just stick with annual oil changes to keep it simple.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil
    By  Chad,  a  Verified Buyer  from  Missouri  on  September 03, 2022
    Best diesel oil yet. Engine idles smoother and feels like acceleration is faster. Cold weather starts are no problem. Highly recommend.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Superior product!
    By  Scott,  a  Verified Buyer  from  Ellerslie  on  August 28, 2022
    Been using Amsoil for many years! Best quality product on the market for synthetic oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Solid
    By  ANTHONY,  a  Verified Buyer  from  maine  on  August 28, 2022
    I use the signature series diesel oil in my powerstroke , and i use this oil in our f150 - great oil results in both.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Amsoil Diesel Oil
    By  RICK,  a  Verified Buyer  from  California   on  August 26, 2022
    Have never used any other oil in my Duramax and will never. Amsoil makes having an account and ordering online super easy. Use in our Triton V10 motor home, GMC Denali, Jeep Wrangler, ‘05 Duramax, Honda Generator, stihl blower etc. lifer!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?