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

Product code : AMEQT-EA

4.9 star rating Read 254 reviews

Customer Rating

4.9

81% would recommend

  • 5 241
  • 4 11
  • 3 2
  • 2 0
  • 1 0

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

4.9 star rating Based on 254 reviews
  • 5 star rating
    A full synthetic 15w40 CI4+
    By  Vipra,  a  Verified Buyer  on  June 12, 2019
    15w40 AME & a 15micron Donaldson P551018 for my annual oil/filter changes. From Southern summers to Northern winters, UOA shows that this combo can't be beaten for my over fueled, compounded decathlete 12v Cummins. Don't ever stop making this outstanding CI4+ oil.
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  • 5 star rating
    15/40 Marine Diesel oil
    By  Usgr,  a  Verified Buyer  from  Poway Ca.  on  June 07, 2019
    Been using since 2003 in Duramax. Handles all climates.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Will definitely only be using amsoil
    By  Easy,  a  Verified Buyer  from  North Georgia  on  June 03, 2019
    Switched to amsoil in my 2006 f250 powerstroke. My truck now starts much better, and runs quieter and smoother!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Does the job !
    By  Raney1999,  a  Verified Buyer  from  North East TX  on  May 29, 2019
    Only oil I've ever used in my 6.7 Cummins for last 100k aside a rotella hear and there. Also use the amsoil oil filter. Works well together !
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  • 5 star rating
    Love using the diesel marine in my truck!
    By  Danny.W,  a  Verified Buyer  from  Frederick MD  on  May 21, 2019
    I've run Amsoil in my 05 Cummins 5.9 for around 200k. And I've used all the different diesel oils Amsoil has to offer from highest of performance to the eco price. But In my leaky 300k plus and climbing work diesel. the marine oil always comes out with just about as much as I put in 10k ago. And the others I would sometimes be up to 3Qt short when drained. Like it's gets so thin that it finds completely new ways to seep out !! But that why I like to order the heavier oil. Lastly my whole truck runs on Amsoil rears,difs,transfer and engine, and I strongly believe that Amsoil is the soul reason why my Cummins runs as good as it does at 310k miles!! Thanks for the spectrum or synthetic lubes to chose from!! Two thumbs high from this guy!!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    This is the only oil I Trust in my Trucks
    By  Cope,  a  Verified Buyer  from  Eastern Oregon  on  March 23, 2019
    Amsoil heavy duty 15w-40 marine diesel oil has proven to me that it will protect my Cummins engines. I have older high mileage Dodge trucks that get driven on the highway, gravel roads in -15F cold and 100F heat and the lab results from my oil samples have continually came back great. At a minimum I put double the factory recommended mileage on this oil before changing, depending on driving conditions.
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  • 5 star rating
    I will keep using this product
    By  ROLAND,  a  Verified Buyer  from  Ligonier, Indiana  on  March 20, 2019
    Reduced engine noise (duramax)
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product been using for many years!
    By  Cummins lover,  a  Verified Buyer  from  South Texas  on  March 19, 2019
    I've been using Amsoil diesel and marine for many years I drive 200 miles a day in my Cummins in and out of petroleum refineries 6 to 7 days a week and I work my truck hard! Amsoil has never let me down! This is a great product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product
    By  Jeff,  a  Verified Buyer  from  Woolford, MD  on  March 11, 2019
    I have been using Amsoil in my 2003 Chevy Duramax for its entire life with great results.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil for boat
    By  Charles,  a  Verified Buyer  from  Richmomd, VA  on  February 13, 2019
    This 15w-40 Marine oil is all I use in both my 2001 300hp Mercruiser boat engines since 2011. Why you might ask? 1) Only oil that has shown to lubricate the turbo blades on my son's boat diesel super-charger. 2) When son's oil hose ruptured at full engine speed, repair mechanic stated that engine only survived due to the oil's lubrication properties.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I would purchase this product again
    By  Kerry,  a  Verified Buyer  from  TEXAS  on  February 12, 2019
    We have been using this product in our 2004.5 Dodge diesel since 2010. The truck had 110K miles on it when we switched over and added the micro-filtration unit. We now have some 329K miles with about 120K miles of that amount while hauling commercial freight. Now back to my daily driver and still using this oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome Oil!!!!!
    By  Chum,  a  Verified Buyer  from  Grand Junction,CO.  on  February 06, 2019
    Product is great. 8-10,000 miles between oil changes. Price is right. You might as well go with the best.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I will always use Amsoil
    By  Matt,  a  Verified Buyer  from  INDIANA  on  February 01, 2019
    It helps my 7.3 powerstroke start better since the injectors are oil fired it will start when 0 degrees without being plugged in
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Oil
    By  Flyoften,  a  Verified Buyer  from  Fort Worth  on  January 27, 2019
    Oil is like a lot of things where the positive traits are hard to quantify. You just have to know it's good and working. I run it in a Ford 6.0 so it has to be good.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I WOULD BUY THIS PRODUCT AGAIN AND AGAIN
    By  LEXUSMAN,  a  Verified Buyer  from  CHICAGO, IL  on  January 23, 2019
    I'VE BEEN USING AMSOIL SINCE 2004 AND I JUST LOVE THESE PRODUCTS. IN MY OPINION AMSOIL IS THE BEST OIL OUT THERE NOTHING COMES EVEN CLOSE. I HAVE A 2002 TOYOTA SIENNA WITH 570.000 MILES YES YOU SAW IT RIGHT 570K MILES AND THAT THING JUST KEEPS ON GOING AND GOING, IT JUST DOESN'T WANT TO QUIT. STILL ORIGINAL ENGINE AND TRANSMISSION. PEOPLE TOLD ME TO GET RID OF IT BUT I TELL THEM IT'S NOT THE TIME YET IT STILL RUNS LIKE A CHAMP AND EVERYTHING IS WORKING ON IT. I USE AMSOIL PRODUCTS ON MY OTHER CARS AS WELL AND A FEW OF MY FRIENDS GOT HOOKED ONCE THEY TRY IT AND THEY NEVER WENT BACK TO THE OIL THEY USED TO USE. THANK YOU AMSOIL FOR YOUR GREAT PRODUCT, KEEP UP THIS AWESOME WORK AND I WISH THAT AMSOIL TO BE AROUND FOR THE NEXT 100 YEARS. BEST WISHES AND GOD BLESS AMSOIL!!!! ISTVAN.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Truck&Tractor
    By  Donkey Boy,  a  Verified Buyer  from  Johnson City Tn.  on  January 22, 2019
    All we use in all our truck&tractor,
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product
    By  Me,  a  Verified Buyer  from  Santa Rosa Ca  on  January 17, 2019
    I have been using this oil sense I bought my 07 Dodge Ram diesel new 12 years ago. I go 15k between oil changes. I'm glad I started using this Oil and the by-pass system when I did. I have 250k on my truck now and plan to go another 250k. Amsoil has been great every time I place an order as well.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I use Amsoil in all my truck gear boxes and diffs
    By  Crowley,  a  Verified Buyer  from  Belgrade MT  on  January 12, 2019
    Have been using heavy duty diesel marine synthetic motor oil in my duramax work truck for last 70,000 miles. Seems to have superior protection and less breakdown under heavy loads and extreme conditions.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great dependable Lubrication
    By  Marv,  a  Verified Buyer  from  Virginia  on  January 04, 2019
    Motor oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I use this oil all winter long
    By  M Grieshop,  a  Verified Buyer  from  Mendon Ohio  on  December 30, 2018
    I run this oil all winter long,every winter
    Bottom Line
    Yes, I would recommend this to a friend.
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