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AMSOIL Signature Series 5W-30 100% Synthetic Max-Duty Diesel Oil

Product code : DHDQT-EA

4.9 star rating Read 1,544 reviews

Customer Rating

4.9

92% would recommend

  • 5 1479
  • 4 45
  • 3 9
  • 2 3
  • 1 8

AMSOIL Signature Series 5W-30 100% Synthetic Max-Duty Diesel Oil

4.9 star rating Based on 1,544 reviews
  • 5 star rating
    Trust
    By  Danny Boy,  a  Verified Buyer  from  Columbus  on  February 12, 2017
    I don't know if my 2013 Ram diesel is protected better by using Amsoil motor oil, but I trust Amsoil research. I believe what Amsoil claims. I can only say this about Amsoil. Only time will tell as the engine ages.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent
    By  100 MPH,  a  Verified Buyer  from  Minneapolis MN  on  February 12, 2017
    I love this oil I rely on it with my lively hood. Great stuff.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best all around
    By  Kevin,  a  Verified Buyer  from  Montague, N.J.  on  February 07, 2017
    2007 Dodge 6.7, engine never sounded smoother. Best investment I've made.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great
    By  Tamworthsat,  a  Verified Buyer  from  Oakwood, TX  on  February 07, 2017
    I would buy this top grade again because I once bought the XL grade and notice a slight drop in mileage.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Nothing else for my diesel truck
    By  Mark,  a  Verified Buyer  from  Las Vegas  on  February 02, 2017
    I have been using Amzoil in my 2008 Dodge Ram 2500 since the first oil change. I currently have 147,000 miles on it and it doesn't burn a drop of oil, runs smooth and has a ton of power. I believe that using a quality oil with regular oil changes is the key. This stuff is not cheap! Neither is this truck! But to replace it is $68,000. I think the Amzoil is going to give me that quarter million mile mark.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I have bought this again and again.
    By  Dabear,  a  Verified Buyer  from  Austin  on  January 30, 2017
    Diesel
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Too much sauce
    By  #NAME?,  a  Verified Buyer  from  Portland OR  on  January 29, 2017
    Perfect
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil you can buy
    By  Big T,  a  Verified Buyer  from  McCool Ms  on  January 24, 2017
    I run this in my 07 duramax it extended my oil change interval from every 5000 miles to every 12000 miles and my truck runs cooler plus I picked up over a mile per gallon on fuel mileage
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I have more faith in this product.
    By  Benny,  a  Verified Buyer  from  Maryland  on  January 22, 2017
    I work my diesel trucks hard. Pull heavy loads 100% of the time. When it's 0° and they start up with quicker oil pressure and less engine clatter, or when it's 95° out and I'm wide open throttle for miles up a long steep grade and my oil temps maintain a steady temperature, I feel more confident my engine will last longer with Amsoil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Yes
    By  Nica,  a  Verified Buyer  from  Chino calif  on  January 15, 2017
    I noticed I get a better fuel gas mileage
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    12 years and counting
    By  L.,  a  Verified Buyer  on  December 27, 2016
    I have been running this oil for over 12 years on my F350 7.3L Diesel. Still running strong.
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  • 5 star rating
    Only the BEST for Me
    By  Frank,  a  Verified Buyer  on  December 26, 2016
    I have been using Amsoil since 1979 and I believe in putting the Best Oil in all my Toys . I use it in my cars,garden tractor , lawn mower , whole house generator , power washer , and my 2 Corvettes ,and in my 2013 Kioti CK35 HST Diesel tractor . I guess you could call me an Amsoil Junkie ??
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  • 5 star rating
    Loyal customer
    By  Arthur,  a  Verified Buyer  on  December 26, 2016
    I just changed the oil in my 2015 with Amsoil for the first time, because the truck came with 2 years of maintenance when bought new, and if you didn't use it your just wasting money.i am a firm believer in Diesel injector clean, I'm on my second Duramax and have never had a fuel related problem. I'll use Amsoil forever. Thanks for great products.
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  • 5 star rating
    I will continue to use Amsoil in all my vehicles.
    By  Mitchell,  a  Verified Buyer  on  December 23, 2016
    Always quality. I run this in my 2009 Ram 6.7 Cummins. Been running nothing but Amsoil since I bought it in 2010 and no issues. I also use Amsoil Signature 5w30 in my hotrods too. I have a 1967 Chevelle SS with Chevrolet crate 502 as well as a 2013 Camaro SS 1LE I never worry about oil related issues with Amsoil.
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  • 4 star rating
    Works good in cold weather.
    By  Clay,  a  Verified Buyer  on  December 22, 2016
    08 Duramax 250k miles and still going strong. -30 here in winter, starts up with good oil pressure no waiting on the pressure gauge to pick up cold oil.
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  • 5 star rating
    Best oil for my Cummins,
    By  Marc,  a  Verified Buyer  on  December 22, 2016
    Only product I use. The BEST! I use it with AMSOIL FF and bypass filters.
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  • 5 star rating
    Best 15-40 diesel oil on the market
    By  Rob,  a  Verified Buyer  on  December 21, 2016
    Excellent product, my 2005 Cummins runs smoother than it ever has. I feel very confident pulling some of the heavy loads that I do, knowing that this oil will stand up to whatever I can put it through.
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  • 5 star rating
    I will stick with Amsoil.
    By  Jeff,  a  Verified Buyer  on  December 20, 2016
    I've been using this in my 2004 Dodge Cummins diesel for 12 years and 120,000 miles and it still runs like it was new.
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  • 5 star rating
    I'm going to continue using this product.
    By  Mark,  a  Verified Buyer  on  December 20, 2016
    Very pleased with the purchase. Regens intervals have increased by a significant margin, particularly in the city driving.
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  • 5 star rating
    I trust Premium 15W-40 Synthetic Diesel Oil in my truck.
    By  Eldon,  a  Verified Buyer  on  December 18, 2016
    This is the only oil I have used in my 2008 Chevy 3500 HD truck since the first oil change. At this time it is not a high mileage truck and generally change the oil due to time limitation and not mileage. However when the truck is being used it is under somewhat severe conditions and I trust Amsoil to take care of it. I will not at this time consider any other engine lubricant for this truck.
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