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Customer Ratings & Reviews

Heavy-Duty Synthetic Diesel Oil 15W-40

Product code : ADPQT-EA

5 star rating Read 113 reviews

Customer Rating

5

96% would recommend

  • 5 111
  • 4 1
  • 3 1
  • 2 0
  • 1 0

Heavy-Duty Synthetic Diesel Oil 15W-40

5 star rating Based on 113 reviews
  • 5 star rating
    Good oil
    By  TOM,  a  Verified Buyer  from  Tennessee  on  September 22, 2022
    this oil by far is the best for my diesel engine. what i do not like is getting weekly, bi-weekly emails with continual free offers from the company when you buy something. it is not like i need to buy oil every few weeks. but i continue to get offers. why not make a list of free offers so when you do buy product and meet a certain dollar value -- you have a list of promotional material to choose from as a free gift from Amsoil. Pick one!!! i would of liked the bottle koozies - which were offered after i placed my order. i did get free shipping which is appreciated, but the continual marketing promotional offers need to be addressed and consolidated. no complaints with the product at all.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    What a difference
    By  Wayne,  a  Verified Buyer  from  PA  on  September 09, 2022
    The oil holds up in all conditions a good bit more Money but seems to be well worth it in the long run for the engine. 7.3 Ford motor
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    2005 lly duramax
    By  PAUL,  a  Verified Buyer  on  September 04, 2022
    Been using it for years
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome Product
    By  NATE,  a  Verified Buyer  from  RI  on  September 02, 2022
    Love this stuff for my 6.4 powerstroke. I used T6 previously and I prefer this over it. At the end of 5000 miles, I believe this oil is in better shape. I’ll continue to use this and will be swapping my differentials over to AMSOIL at the next change. Thanks!!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil
    By  CODY,  a  Verified Buyer  from  Ks  on  August 29, 2022
    Always a great product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil
    By  MICHAEL,  a  Verified Buyer  from  Menifee. California   on  August 24, 2022
    It's real synthetic oil, unlike other brands that are allowed to claim full synthetic while using super filtered black sludge from the ground. The FTC threw it's hands in the air and said: " call it whatever you want to "
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Only oil I use in my 2002 Ford Superduty Truck
    By  DOUG,  a  Verified Buyer  from  Calif.  on  July 31, 2022
    Only oil I use in my 2002 7.3 diesel superduty 3/4 truck. 234K miles so far. Love the longer oil change intervals. Hope to keep this truck on the road for many more miles. I have driven it into Canada and all over the Pacific Northwest. A great piece of mind knowing I have the added protection. I can easily recommend this oil for others.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Furnace oil
    By  DENNIS,  a  Verified Buyer  from  Lenexa Kansa  on  July 29, 2022
    Love this product seems to make engine run quieter. Love that it can be purchased in 10 quart jug.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    XL 10W-40 Synthetic Motor Oil
    By  Martin,  a  Verified Buyer  from  Nv  on  July 28, 2022
    Best damn oil ever, I not only use this diesel oil I use Amsoil in everything my cars my motorcycles, ATV, generator, transmissions. Literally everything runs stronger and cooler dropped my Harley's running temperature 15-20 degrees!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good oil for my tractor
    By  Louis,  a  Verified Buyer  from  WV  on  July 25, 2022
    I use this oi in my 2006 John Deere 3203 compact utility tractor. Besides miscellaneous jobs throughout the year, I brush-hog a couple of acres in the fall. The oil lever never goes down.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil period.
    By  JIMMIE,  a  Verified Buyer  from  Deridder La.   on  July 21, 2022
    I was able to extend my oil changes with Amsoil, and it stays clean longer. My 7.3 powerstroke runs better. I want use anything else.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel
    By  STEVE,  a  Verified Buyer  from  Louisiana   on  July 05, 2022
    I use only this oil in my 2018 Duramx.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil I’ve ran in my vehicle
    By  RICHARD,  a  Verified Buyer  on  June 29, 2022
    Awesome oil couldn’t be happier with it
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good stuff
    By  Anthony,  a  Verified Buyer  from  MN  on  June 20, 2022
    Driving 07 Chevy LBZ run this in the summer for the warm temperatures so far I have not had a problem
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Synthetic Diesel Oil
    By  WILLIAM,  a  Verified Buyer  from  Eastern Virginia  on  June 04, 2022
    I’ve got a rare 2003 F250 with the 7.3 in it, bought it new. I’ve been running AMSOIL Synthetics in it (engine, transmission and differentials) with the dual bypass filter system since approximately 2010. Zero mechanical issues. Sure it may cost a little more however, the protection and piece of mind are worth it! Wouldn’t use anything else.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Oil
    By  Bones,  a  Verified Buyer  from  Walla Walla WA  on  June 02, 2022
    Heavy Duty 15-40 Amsoil is a great oil for my 7.3 in my 2003 F-350 my engine is protected from normal wear to the engine I cannot say enough to the protection it gives me for my engine! Thank you AMSOIL.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good oil to run in my F350
    By  TY,  a  Verified Buyer  from  Calgary Alberta   on  May 28, 2022
    Lasts longer worth the price for the protection and the mileage/hours on my trucks and equipment.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best Oil
    By  NOAH,  a  Verified Buyer  on  May 27, 2022
    Slowly Switching all my trucks fluids over to Amsoil. Truck seems to run smoother now that I’ve switched the engine oil over.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Does the job
    By  ANDY,  a  Verified Buyer  on  May 19, 2022
    12 quarts of oil does the job perfect for a 6.7 Cummins for it to go tow 10k no problem.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent Oil
    By  ROGER,  a  Verified Buyer  from  Dalmeny,Sask  on  May 12, 2022
    Anywhere I use oil or fuel treatment I use Amsoil only excellent product
    Bottom Line
    Yes, I would recommend this to a friend.
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