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DOMINATOR 20W-50 Competition Diesel Oil

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The Confidence to Compete, The Protection To Win

AMSOIL DOMINATOR® 20W-50 Competition Diesel Oil is designed for professionals and enthusiasts who want a step up in diesel protection. It is specifically designed for high-horsepower diesel engines and delivers the benefits most important to diesel competitors, including robust durability, outstanding bearing protection and the ability to withstand the extreme pressures and temperatures common to diesel competition.
AMSOIL DOMINATOR® 20W-50 Competition Diesel Oil is designed for professionals and enthusiasts who want a step up in diesel protection. It is specifically designed for high-horsepower diesel engines and delivers the benefits most important to diesel competitors, including robust durability, outstanding bearing protection and the ability to withstand the extreme pressures and temperatures common to diesel competition.

DOMINATOR 20W-50 Competition Diesel Oil



Whether competing in sled pulls, drag races or dyno challenges, competitors using DOMINATOR Competition Diesel Oil enjoy the confidence and security that come with providing their diesel trucks maximum protection and performance.

Wear Protection
Racing and high-performance diesel engines are modified to deliver maximum horsepower and torque. Their powerful designs create shearing forces that can cause oils to lose viscosity, leaving bearings, pistons and other components vulnerable to wear and failure. DOMINATOR 20W-50 Competition Diesel Oil delivers 50 percent more film thickness* to withstand high cylinder pressures and protect against wear. It is heavily fortified with zinc and phosphorus anti-wear additives to provide additional protection against scuffing and wear in severe conditions.

*compared to the 3.5cP HTHS limit for SAE 15W-40

HTHS

Viscosity Control
High-horsepower diesel engines push a lot of fuel, leading to fuel dilution. Fuel reduces the oil's viscosity. As the oil becomes thinner, it compromises the lubrication of critical components, increasing wear. DOMINATOR Competition Diesel Oil's robust formulation helps offset the damaging effects of fuel dilution by maintaining its protective viscosity longer.

Withstands Turbocharger Heat
Over time, turbos can suffer reduced performance or catastrophic failure. DOMINATOR Competition Diesel Oil is designed with an extremely durable 20W-50 synthetic formulation that contains maximum levels of oxidation-inhibitor additives to resist harmful oxidation and provide exceptional resistance to deposit formation, preserving turbocharger performance and life.

APPLICATIONS
Use in performance-modified diesel engines that require any of the following specifications:

  • API CK-4, CJ-4, CI-4+, CH-4
  • Cummins 20081/20086
  • Mack EO-O/EOS-4.5
  • Volvo VDS3/VDS4/VDS4.5
  • Caterpillar ECF-2, ECF-3, ECF-1-a
  • Renault RLD-3/RLD-4
  • Chrysler MS 10902
  • Ford WSS-M2C171-F1

EHD Film Thickness

COMPATIBILITY
DOMINATOR 20W-50 Competition 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
DOMINATOR Competition Diesel Oil provides lasting protection for multiple events. Use oil analysis to determine appropriate drain interval.

Note: When not competing, follow OEM1 drain intervals or extend drain intervals with oil analysis.

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

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.ca or upon request at (715) 392-7101. Keep Out of Reach of Children. Recycle used oil and bottle.

AMSOIL PRODUCT WARRANTY
AMSOIL products are backed by a Limited Liability Warranty. For complete information visit www.amsoil.ca/warranty/.

* 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.

DOMINATOR 20W-50 Competition Diesel Oil



DOMINATOR 20W-50 Competition Diesel Oil

  • 5
    20W50 for new GM 6.6L Diesels
    By  WILLIAM,  a  Verified Buyer  from  Camden, NC  on  January 08, 2022

    Describe the issue

    This is very good oil for GM diesels. The current engine has a crankshaft relate noise at normal operating temp (NOT), I believe due to an inferior oil pump design. Below 31PSI, a crankshaft related noise is discernable. I have written GM on possible solutions that are cheaper than replacing the engine under warranty. The 20W50 helps keep the oil pressure above 32PSI at idle which stops the noise. In the colder months I have cut the oil 50/50 with 15W40 DME, but once at NOT, the crankshaft noise does come back. This engine seems to need 30W oil to prevent the noise at NOT at idle. I am unable to find a good 30W diesel oil with API CI-4 or CK-4. The 20W50 from AMSOIL is the best at helping this situation until they make a 30W or 30W40 for this engine.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Damaged leaking container no response from Amsoil
    By  BARRY,  a  Verified Buyer  from  Sonora Ca  on  November 25, 2021

    Describe the issue

    The product is great and I have ordered many times. My last order arrived with a punctured leaking container. Tried to contact Amsoil with photos but received NO response. Could do much better with customer service.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Great Oil!
    By  ERIC,  a  Verified Buyer  on  November 15, 2021

    Describe the issue

    Great oil, not only for competition motors. You can hear and feel a difference in the engine and idle.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Best Diesel Oil
    By  Sewerman,  a  Verified Buyer  on  September 04, 2021

    Describe the issue

    I use this in my 2019 NPRHD Box Truck. It provides exceptional protection compared to Mobil 1
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    Diesel oils.
    By  Eugene,  a  Verified Buyer  from  Brooklyn, NY  on  May 21, 2021

    Describe the issue

    Excellent quality oil. I would not be afraid to say " state of the art ".
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5
    1st order good 2nd never showed up
    By  AUSTIN,  a  Verified Buyer  on  April 17, 2021

    Describe the issue

    The motor oil ran awesome but I’ve been waiting on my last order for 2 months and it’s still a no show... unimpressed with my shipping experience but this oil is gold!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?