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DOMINATOR 20W-50 Competition Diesel Oil

Product code : DCOQT-EA

5 star rating Read 6 reviews

Customer Rating

5

100% would recommend

  • 5 6
  • 4 0
  • 3 0
  • 2 0
  • 1 0

DOMINATOR 20W-50 Competition Diesel Oil

5 star rating Based on 6 reviews
  • 5 star rating
    20W50 for new GM 6.6L Diesels
    By  WILLIAM,  a  Verified Buyer  from  Camden, NC  on  January 08, 2022
    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.
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  • 5 star rating
    Damaged leaking container no response from Amsoil
    By  BARRY,  a  Verified Buyer  from  Sonora Ca  on  November 25, 2021
    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.
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  • 5 star rating
    Great Oil!
    By  ERIC,  a  Verified Buyer  on  November 15, 2021
    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.
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  • 5 star rating
    Best Diesel Oil
    By  Sewerman,  a  Verified Buyer  on  September 04, 2021
    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.
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  • 5 star rating
    Diesel oils.
    By  Eugene,  a  Verified Buyer  from  Brooklyn, NY  on  May 21, 2021
    Excellent quality oil. I would not be afraid to say " state of the art ".
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    1st order good 2nd never showed up
    By  AUSTIN,  a  Verified Buyer  on  April 17, 2021
    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.
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