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AMSOIL 15W-40 Heavy-Duty Diesel and Marine Oil

Product code : AMEQT-EA

4.9 star rating Read 265 reviews

Customer Rating

4.9

82% would recommend

  • 5 250
  • 4 13
  • 3 2
  • 2 0
  • 1 0

AMSOIL 15W-40 Heavy-Duty Diesel and Marine Oil

4.9 star rating Based on 265 reviews
  • 5 star rating
    By  JIM,  a  Verified Buyer  from  simi valley, ca  on  January 25, 2021
    I have been running this oil for 15 years in my 2005 superduty 6.0 diesel. This truck pulls a 16,000 lb fifthwheel many miles a year. Engine does not use any oil, have not had any injector sticking, and no turbo coking. Great customer service and lighting fast shipping.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I believe in this product.
    By  RONALD,  a  Verified Buyer  from  Elk Grove, California   on  January 23, 2021
    I have used many oil in this truck over the last 31 years of ownership. When I put this in my truck for the first time, I immediately heard a distinct difference on fire up. It softened the harsh rattle somehow. I know this sounds silly but when you own a vehicle as long as I have this one, you notice any difference in operation. It also uses less oil. I have gone through 2 oil change cycles with this product, and each time have not had to add but 1 quart every 3000 miles, versus every 1000. That is a huge difference. I am a convert. I am even putting this in my car now.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  HAL,  a  Verified Buyer  from  lake havasu city az. 86404  on  January 08, 2021
    I have been using amsoil diesel/marine in my 2004 dodge cummins since it was new, never had any issues. the truck has 186000 miles on it and sometimes the oil doese't get changed for 6000 miles but always has plenty of lubricity when changed. Hal
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    better for cold starts
    By  DERICK,  a  Verified Buyer  from  Virginia  on  January 08, 2021
    I have a Kubota 8200 farm tractor it has a low oil pressure shut-off in cold weather using conventional motor oil same weight it would crank and shut off using Amsoil diesel marine this stopped so oil is getting through the engine quicker so now I use in all our farm equipment
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Nothing but the best
    By  FIN,  a  Verified Buyer  from  Florida  on  January 01, 2021
    The absolute best for my 2002 7.3L Diesel Excursion.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  JAMES,  a  Verified Buyer  from  Home  on  December 12, 2020
    I always liked Amsoil products. Just put it in my tractor and i will compare to the old oil after I put more hours on it.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  JOSEPH,  a  Verified Buyer  on  December 05, 2020
    Great oil, I use it in my 2006 Century Freightliner, I have over a million miles on it. Wouldn't trust any other oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  KENNETH,  a  Verified Buyer  on  December 01, 2020
    I have a Chevy Silverado 3500 year 2008 410,000 miles on the truck love this product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Years of success
    By  ALLEN,  a  Verified Buyer  from  Northern Alberta, Canada  on  November 20, 2020
    I’ve been using this Series 3000 in my 2006 F350 with the 6.0 diesel. Yes the infamous 6.0. These are great engines built with extremely high tolerances that requires religious oil changes every 200 hours. By using the Series 3000 I have extended my hours up to 300. I could go more as per oil sample results. But typically this is right around the one year mark anyways. As you have probably heard, the 2006 F350 is one of the most stolen trucks in North America. I can attest to this as mine has been taken twice now. Once from work and once right from my home address. Yes I have a security system on it now. But back to the oil. In both thefts, the engine was abused enough to crack the heads and ruin the turbo. Yep. Both times. But the bottom end of my engine has never been touched and I have not had to change my high pressure oil pump either. I am pushing close to 400,000km on it now and it still pulls hard. I purchased it with 120,000 km on it and immediately changed over to Amsoil and put a 75hp tune in it. Other than the thefts, I have never had an issue and I run it year round, summer and winter. Would never think of using anything else.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  PAUL,  a  Verified Buyer  on  November 17, 2020
    Over 200,000 miles on F-150 using this oil no issues what so ever with engine.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  Anonymous,  a  Verified Buyer  on  October 23, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good Product
    By  Anonymous,  a  Verified Buyer  from  Belgrade, MT  on  October 19, 2020
    Have been running in 04 duramax 3/4 ton for 100,000 miles with regular oil change intervals between every 3500 to 5000 miles in a work truck that has towed heavy loads or been under stress for most of its life. Switched to synthetic amsoil at 65,000 miles in engine, plus transmission and all the boxes. Has 179,000 + miles on it now and is still running and working strong. I believe the amsoil and regular oil change intervals has made a difference in the longevity of trucks power train components.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The... best oil for pre Anniston
    By  Anonymous,  a  Verified Buyer  on  October 15, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best of the best
    By  RW,  a  Verified Buyer  from  Missouri  on  October 15, 2020
    I recommend AmsOil products all the time to friends and family. Well worth the investment.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good product
    By  Flint,  a  Verified Buyer  on  October 17, 2019
    it's a good product but I don't like the gallon jug design. They're hard to pour.
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  • 5 star rating
    Have been using this oil for 15 years.
    By  Leslie,  a  Verified Buyer  on  October 16, 2019
    Have used this oil in my Duramax since it finally broke in at 70,000, I now have 255,000 on it and every oil test came with 50% oil life after 10,000. I do a lot of short trips along with really long trips towing.
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  • 5 star rating
    Yes
    By  Corey,  a  Verified Buyer  on  October 10, 2019
    Makes changes a snap in my duramax. The 2 1/2 gallon jug fills her to the top of the stick. Great product and easy to order too
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  • 5 star rating
    i have bought this oil since 2005 and will continue
    By  Billy,  a  Verified Buyer  on  October 08, 2019
    I have used amsoil in my 2003 dodge ram 3500 the oil, performs very well has always checked good with an oil analysis 222,000 miles without ant oil related problems towing horse trailers and now a 36ft 5th wheel
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  • 5 star rating
    Driver
    By  Yaremchuk,  a  Verified Buyer  on  October 07, 2019
    Very good quality.
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  • 5 star rating
    Best for Diesels.
    By  Kenneth,  a  Verified Buyer  on  October 04, 2019
    Boatload of additive for Excellent TBN analysis between extended oil changes.
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