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

Product code : DEOQT-EA

Maximum-duty protection for your hardest-working diesel engines

Protect your investment in diesel power and confidently extend drain intervals with our top-grade synthetic diesel oil. AMSOIL Signature Series Max-Duty Synthetic Diesel Oil delivers 6X better wear protection than required by the Detroit Diesel DD13 Scuffing Test for Specification DFS 93K222. Advanced synthetic technology provides excellent viscosity control and outstanding extreme-temperature performance, while minimizing oil consumption. The result: protection that’s boosted to the max.
Protect your investment in diesel power and confidently extend drain intervals with our top-grade synthetic diesel oil. AMSOIL Signature Series Max-Duty Synthetic Diesel Oil delivers 6X better wear protection than required by the Detroit Diesel DD13 Scuffing Test for Specification DFS 93K222. Advanced synthetic technology provides excellent viscosity control and outstanding extreme-temperature performance, while minimizing oil consumption. The result: protection that’s boosted to the max.

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



Maximum Engine Protection
Wear on rings and cylinder liners leads to increased oil consumption and loss of compression, resulting in reduced horsepower and fuel economy. Independent testing shows Signature Series Max-Duty delivers 6X more wear protection than required by the Detroit Diesel DD13 Scuffing Test for Specification DFS 93K222, delivering extra protection so you can push your diesel with peace of mind.

Viscosity Control
Using top-tier synthetic base oils, Signature Series Max-Duty is naturally resistant to oxidation and the thickening effects of soot contamination. That, along with boosted detergent/dispersant additives, keeps soot particles suspended independently, helping prevent the formation of larger, wear-causing particles. Viscosity increase is minimized and soot-related wear is controlled. Lower volatility also helps Signature Series Max-Duty Diesel Oil retain its viscosity after high-temperature service for maximum engine protection and efficiency.

Excels in Extreme Temperatures
Signature Series Max-Duty Synthetic Diesel Oil resists thermal (heat) breakdown better than conventional and competing synthetic diesel oils. Unlike conventional oils, Signature Series contains no wax, staying fluid in sub-zero temperatures for easier starting, improved oil flow and reduced wear. Signature Series 0W-40 (DZF) has a broad viscosity range that offers 4X better cold-cranking ability than a 15W-40 oil in the ASTM D5293 cold-cranking viscosity test, making it excellent for use in both hot-operating engines and cold-weather starting extremes.

Minimizes Oil Consumption
Signature Series Max-Duty has a low rate of volatility (burn-off), reducing oil consumption during operation and passing less oil vapor into the combustion chamber. It provides up to 76 percent less oil consumption than required by the API CK-4 standard in the Caterpillar-1N oil consumption test.

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. K Based on industry standard testing using the NMMA FC-W Rust Test. *Based 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. All products advertised here are developed by AMSOIL for use in the applications shown.

Oil Consumption

APPLICATIONS
Use in diesel engines and, where appropriate, gasoline engines requiring any of the following specifications:

  • API CK-4/SN, CJ-4, CI-4+, CF
  • Volvo VDS4.5, VDS4, VDS3
  • Mack EOS-4.5, EO-O
  • Renault RLD-4, RLD-3
  • Cummins CES20086, CES20081
  • Caterpillar ECF-2, ECF-3, ECF-1-a
  • DDC 93K218, 93K215, 93K214
  • DFS 93K222
  • ACEA E9, E7
  • MB 228.31
  • MAN 3575
  • MTU Type 2.1, II, I
  • JASO DH-2
  • Allison TES439
  • Deutz DQC III-10LA
  • Scania LA-2
  • Chrysler MS 10902
  • Ford WSS-M2C171-F1

Official Oil

COMPATIBILITY
AMSOIL Signature Series Max-Duty Synthetic Diesel Oil is compatible with other conventional and synthetic engine oils. Mixing AMSOIL diesel oils with other oils, however, will shorten the oil's life expectancy and reduce the performance benefits. AMSOIL does not support extended drain intervals where oils have been mixed.

Aftermarket oil additives are not recommended for use with AMSOIL synthetic diesel oils.

SERVICE LIFE
Diesel Engine Service Life
Heavy-Duty On-/Off-Road: Three times (3X) OEM1 recommendation, not to exceed 60,000 miles/600 hours or one year, whichever comes first.

Turbodiesel Pickup: Two times (2X) OEM1 recommendation, not to exceed 25,000 miles or one year, whichever comes first.

Competition Service Life: Provides lasting protection for multiple events. Use oil analysis to determine appropriate drain interval.

Gasoline Engine Service Life
Two times (2X) OEM1 recommendation, not to exceed 15,000 miles or one year, whichever comes first.

Drain intervals may be extended further with oil analysis.

Note: Extended drain intervals are not recommended for performance-modified engines, when using biofuels containing more than 10 percent ethanol or 15 percent biodiesel (B15) or for 2007-2009 Caterpillar* C13 and C15 on-highway engines. Extend drain intervals beyond OEM recommendations in these instances only with oil analysis. Note: 2007-2010 Dodge**, Ford** and GM** turbodiesel pickups are also not recommended for extended drain intervals when using DHD.

1Refer to your owner's manual for OEM drain interval recommendations and guidelines for severe and normal service.

PRODUCT WARRANTY
Using AMSOIL synthetic lubricants or practicing extended drain intervals does not void your new vehicle or equipment manufacturer’s warranty. All AMSOIL lubricants and filters are covered by the AMSOIL Limited Warranty. For complete information visit www.amsoil.com/about/guarantee/.

Warranty Secure

HEALTH & SAFETY
This product is not expected to cause health concerns when used for the intended application and according to the recommendations in the Safety Data Sheet (SDS). An SDS is available online at www.AMSOIL.com or upon request at (715) 392-7101. Keep Out of Reach of Children. Recycle used oil and bottle.

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



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

  • 5
    By  MIKE,  a  Verified Buyer  from  Dodgeville Wisconsin   on  January 22, 2021

    Describe the issue

    The top 2 best, most honest mechanics I know recommend Amsoil. I've been using it for a couple years now and agree it's the best. Most noticeable to me is starting my diesel in the winter has improved as I don't have to plug it in anymore and it warms up faster. Also like not having to change the oil as often. Worth the money. Mike
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  RICKY,  a  Verified Buyer  on  January 21, 2021

    Describe the issue

    This is very good oil for my 6.7 diesel. This is the best oil I have used in any of my diesel trucks.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  MATTHEW,  a  Verified Buyer  on  January 21, 2021

    Describe the issue

    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    2.5 Gallon size
    By  SCOTT,  a  Verified Buyer  on  January 20, 2021

    Describe the issue

    I didn't realize there was such a size until I browsed the Amsoil site. I run the PPE filter on my Duramax so a big jug and small jug does the job with no leftovers. So convenient to get order sent to my home.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Only oil for my trucks
    By  ANDREW,  a  Verified Buyer  on  January 19, 2021

    Describe the issue

    Love this oil, I have been using it for years
    Bottom Line
    Yes, I would recommend this to a friend.
  • 4
    Satisfied as Usual with Amsoil
    By  SCOTT,  a  Verified Buyer  from  Mississippi  on  January 19, 2021

    Describe the issue

    Quick delivery for a superior product, use Amsoil in all my vehicles
    Bottom Line
    Yes, I would recommend this to a friend.
  • 4
    By  ALBERT,  a  Verified Buyer  from  Cold Lake, Alberta, Canada  on  January 19, 2021

    Describe the issue

    I did find that this lubricant worked on reverse in saying it will increase fuel mileage, my with backwards. I still continue using this oil for my 2015 GMC 3500 HD Diesel engine
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    best oil
    By  RODNEY,  a  Verified Buyer  on  January 19, 2021

    Describe the issue

    best oil fastest service
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    best ol
    By  RODNEY,  a  Verified Buyer  on  January 19, 2021

    Describe the issue

    best oil and fastest service
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    The best
    By  WAYNE,  a  Verified Buyer  from  Chilliwack  on  January 18, 2021

    Describe the issue

    Tried many oils when I got my Duramax and this is the only stuff that takes the ticking away
    Bottom Line
    Yes, I would recommend this to a friend.