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AMSOIL Signature Series 15W-40 100% Synthetic Max-Duty Diesel Oil

Product code : DMEQTC-EA

4.9 star rating Read 1,537 reviews

Customer Rating

4.9

92% would recommend

  • 5 1472
  • 4 45
  • 3 9
  • 2 3
  • 1 8

AMSOIL Signature Series 15W-40 100% Synthetic Max-Duty Diesel Oil

4.9 star rating Based on 1,537 reviews
  • 5 star rating
    Duramax
    By  BARRY,  a  Verified Buyer  from  Iowa  on  April 12, 2022
    Great products!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good Oil
    By  DAVID,  a  Verified Buyer  from  Ohio  on  April 12, 2022
    After using Rotella T6 and being forced to go somewhere else for oil due to shortages, I found my full time replacement. This is a good oil to run in the Ecodiesel and hits all the check marks on what Chrysler wants for the oil spec. Slightly spendy, but a good oil to run in the truck.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oill
    By  ANTHONY,  a  Verified Buyer  on  April 12, 2022
    Like the product if your going to keep your vehicle long term.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    great stuff
    By  WILLIAM,  a  Verified Buyer  from  Washington  on  April 11, 2022
    as advertised love this product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Full Circle
    By  DMAX,  a  Verified Buyer  from  Indiana   on  April 11, 2022
    So I first started using Amsoil in 1980. I had a 1979 Chevy K20 4x4 with a 4 speed trans. I had changed all lubricants to Amsoil. I remember how impressed I was when pushing in on the clutch in sub zero weather and the truck not feeling like I just hit the brakes. Fast forward to today. I now have a 2015 Duramax and have been using Rotella T6. Due to supply chain issues T6 is getting hard to find in my area so I thought let’s give Amsoil a try again. So after about 3500 miles I have noticed that the Truck is running around 15 to 20 psi higher oil pressure than with T6. Not sure why just an observation.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best diesel oil
    By  DAVID,  a  Verified Buyer  from  OK  on  April 09, 2022
    Been running this oil in my 2004 Chevy LLY Duramax for over 10 years. 218K miles. Still waiting on the EA052 oil filter
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    My new oil!
    By  DAVID,  a  Verified Buyer  on  April 08, 2022
    I now have my favorite oil! I will never be using any other oil then this amazing product..
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Product
    By  MICHAEL,  a  Verified Buyer  from  Valley Springs, CA  on  April 07, 2022
    Love Amsoil products!! Nothing better in my opinion. I run Amsoil in everything I own!!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Signature series max duty 15w-40
    By  MAHLON,  a  Verified Buyer  from  Westlake, LA.  on  April 07, 2022
    I have used this product exclusively in my 2018 duramax. I have done a couple of used oil analysis as well. This oil is great. Wouldn't use anything else. The customer service is great too!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Signature Series Max-Duty Synthetic Diesel Oil 15W-40
    By  FRANK,  a  Verified Buyer  from  NW Arkansas  on  April 05, 2022
    I have great confidence in this oil. I like the idea of extended (25,000 mls) oil change intervals with twice the protection. I find my oil pressure is 3lbs greater when operating at 2000 RPM than with Shell Rotella 15w40 Diesel Oil. Shell Rotella maybe cheaper by the mile, but it has only half the protection.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Signature series diesel oil
    By  WILLIAM,  a  Verified Buyer  on  April 04, 2022
    I run this oil in my Silverado duramax I have. I like the better protection this oil provides.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    First Time User
    By  ROGER,  a  Verified Buyer  from  W.V.  on  April 03, 2022
    Order arrived quickly, about two or three days. Just changed the oil everything looks good so far.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Maximum Protection
    By  ALAN,  a  Verified Buyer  from  Sunapee   on  April 03, 2022
    I have been using Amsoil for years and a happy customer. I had been purchasing my oil from a coworker who retired. I wanted to remain a customer so I became a member. Thank you Amsoil for your quality products.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Arrived leaking
    By  RICK,  a  Verified Buyer  on  April 03, 2022
    Arrived fast, however 1 container was leaking had to transfer to another container. A real mess on my steps
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  CARLOS,  a  Verified Buyer  from  Texas  on  April 02, 2022
    This oil is awesome, it feels completely different from other competitors. I will never again use any other oil in any of my trucks.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  MICHAEL,  a  Verified Buyer  from  PA  on  March 30, 2022
    I have been using Amsoil for over 10 years great product all around. I have 2001 F350 w/7.3 diesel. 249,000 miles. Still get great gas mileage. Fast shipping
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Super product for extreme Minnesota cold
    By  TONY,  a  Verified Buyer  from  St paul mn  on  March 29, 2022
    Super lube for winter , much more quiet on startup, dealers use conventional 15w40 so watch out it does not flow if you choose dealer service exactly why I switched
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Use the best
    By  ROY,  a  Verified Buyer  from  Maine   on  March 28, 2022
    I use Amsoil in all my vehicles. My 2020 Ram 2500 with a 6.7 Cummins Takes 13 qts due to the fact I’m using The Amsoil bypass filter set up. With the rising oil prices i can go twice if not more on an oil change. This stuff is The best.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel motor oil
    By  Glenn,  a  Verified Buyer  from  Charlotte,NC  on  March 26, 2022
    This is my first time using Amsoil. I have read great reviews so I’m looking forward to long engine life and great performance on my 2021 Ford F 250 6.7 L diesel truck while using this great product with real life and real world testing.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Immediately lessened engine noise. Ran smoother as well.
    By  RICHARD,  a  Verified Buyer  from  Arizona  on  March 24, 2022
    First time using this. Immediate results as far as less noise and smoother running engine!
    Bottom Line
    Yes, I would recommend this to a friend.
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