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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

Data Bulletin

Warranty

SDS



Signature Series Max-Duty Synthetic Diesel Oil 5W-40

  • 5 star rating
    🇺🇸🇺🇸🇺🇸
    By  JASON,  a  Verified Buyer  on  January 21, 2023
    Great products and 💯🇺🇸 made. Customer for life!!! I love the guaranteed protection on the parts the oils come in contact with. Switched from R**** P***** after using them for 13 years and can tell my motor is running smoother.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I am amazed.
    By  jason,  a  Verified Buyer  from  NJ  on  January 21, 2023
    I used this for my newly rebuilt 1990 Jeep YJ 4.7 stroker. 4.2 Jeep motors were known for noisey lifters after the engine is up to temp. This oil has dramatically quieted my motor down. My oil pressure is 7psi higher at idle and 12 psi higher under load. This is compared to Rotella T6 15w-40. My cold start lifter tap is HALF the time (in seconds) that Rotella was. Let's say Rotella was 2-3 seconds of noise. Amsoil Diesel 5w-40 is 1.5 seconds of tap in the morning on a cold start. I was a faithful Rotella user for years. Well now I am loyal to Amsoil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    oil upgrade
    By  ALLAN,  a  Verified Buyer  from  OK  on  January 18, 2023
    wanted up upgrade to the 5W-40 for the winter starting performance over my previous 15W-40. The oil pressure does come up a little faster.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    oil upgrade
    By  20Tremor,  a  Verified Buyer  from  21771  on  January 18, 2023
    made the switch to Amsoil based on previous experience using 10W-30 in a 86 Bronco II and a 88 straight 6 F250. Also, reviews from a couple of diesel forums gave good reviews. i have made 3 oil changes to my 6.7L and the oil coming out doesn't seem to be as gritty as the syn. penz. i was using.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great Product
    By  MIKE,  a  Verified Buyer  from  Lancaster, SC.  on  January 14, 2023
    I decided to use this oil in my 2015 F-350. It seems to be doing much better than the old oil I was using. I will be using this oil from now on.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Good oil
    By  THOMAS,  a  Verified Buyer  from  Kamloops B.C.  on  January 14, 2023
    Good oil for a reasonable price super quick shipping. Great staff to deal with.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great for heavy duty protection
    By  FERNANDO,  a  Verified Buyer  from  Vancouver wa  on  January 08, 2023
    It gives peace of mind knowing that the engine is protected.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great Product
    By  QUINTON,  a  Verified Buyer  on  January 08, 2023
    Exceeds standard. Great product
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great product
    By  PIERRE,  a  Verified Buyer  from  Casselman Area  on  January 05, 2023
    Have been using Amsoil for over 38 years
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Cummins 6.7 Requirement
    By  WYATT,  a  Verified Buyer  from  SC  on  January 05, 2023
    It’s comforting knowing your using the best product available.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?