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

Product code : DEOQTC-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

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
    So far so good 👍
    By  MATT,  a  Verified Buyer  from  New Hampshire  on  November 29, 2024
    I have always used amsoil products and will continue to use them, this diesel oil was exactly what my high horsepower heavy hauling Duramax needed
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Signature Series 15w40 Syntheric Max Duty Diesel oil
    By  ROBERT,  a  Verified Buyer  on  November 24, 2024
    the Best oil around. Engine seems to run quieter. Also improved gas millage
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great oil
    By  DAVID,  a  Verified Buyer  from  Baltimore   on  November 18, 2024
    Have nothing but good luck with this oil and my Amsoil dealer it’s the best to deal with!! There to help anytime I need it or just to place my order.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    I would recommend
    By  CHRIS,  a  Verified Buyer  on  November 18, 2024
    I run this in all my diesel’s trucks and Volkswagen diesel car work very well for me
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Oil change
    By  DANA,  a  Verified Buyer  from  New phila  on  November 17, 2024
    Exactly what I ordered and came before delivery date which is very good
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Don’t know what you’re asking
    By  GERALD,  a  Verified Buyer  on  November 14, 2024
    Good product and service
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    No oil is better—none!
    By  STURE,  a  Verified Buyer  from  Elk River, MN  on  November 12, 2024
    No oil is better—none! I have used this product since May 2020. My diesel engine purrs like a content kitten, and I have gone 15K miles between oil changes.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    15-40 diesel oil
    By  TONY,  a  Verified Buyer  from  Maryland  on  November 11, 2024
    I have been using this oil in my 2015 3500 Silverado with a Duramax diesel. I started using the oil at 10,000 miles. I now currently have 198,000. It doesn’t use oil and it does not leak oil. I change the oil every 7500 miles. Absolutely love this product.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel Syn. Oil
    By  BRIAN,  a  Verified Buyer  from  Az.  on  November 10, 2024
    Great oil to use on all your toys !
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil on the market
    By  LUIS,  a  Verified Buyer  from  Live Oak, TX   on  November 10, 2024
    This is seriously the best oil on the market for gas and diesel trucks. Comes in just a few days. I will always use Amsoil
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?