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Customer Ratings & Reviews

Heavy-Duty Synthetic Diesel Oil 5W-40

Product code : ADOQT-EA

4.9 star rating Read 71 reviews

Customer Rating

4.9

99% would recommend

  • 5 67
  • 4 4
  • 3 0
  • 2 0
  • 1 0

Heavy-Duty Synthetic Diesel Oil 5W-40

4.9 star rating Based on 71 reviews
  • 5 star rating
    Great product been using it for awhile now
    By  JARRED,  a  Verified Buyer  on  March 16, 2023
    Great product been using it for awhile now!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    4x 5-40 diesel oil
    By  DUANE,  a  Verified Buyer  from  lakewood ca   on  February 15, 2023
    amsoil is all in use in everything i drive
    Bottom Line
    No, I would not recommend this to a friend.
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  • 5 star rating
    Great product
    By  Eric,  a  Verified Buyer  from  MT  on  January 03, 2023
    Great product. Takes the smoke out of the back end and makes cold starts effortless.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  JIM,  a  Verified Buyer  from  Arizona  on  December 31, 2022
    I used this oil for my first oil change (2022 F-350 Diesel). The engine starts and runs quieter than with the factory fill.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil
    By  MATT,  a  Verified Buyer  on  December 31, 2022
    Love this stuff
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The good stuff
    By  DAN,  a  Verified Buyer  from  Massachusetts   on  December 25, 2022
    Used to run rotella t6 but switched to this stuff ever since I discovered the preferred customer program and will never go back! Run it in my powerstroke and my tractor now as well
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil Quality
    By  JIM,  a  Verified Buyer  from  Florida  on  December 25, 2022
    Many oils are not described about the abilities to protect the engine. Amsoil does. As well with filters like the two sets of Amsoil double filters I have installed on two trucks their filters are far superior in cleaning oil. Most products sold today are poor quality with advertising. Amsoil has stuck to consumer education and better products. All our equipment uses Amsoil oil and filters in order to avoid other oil company scams. We removed the 2015 6.7 diesel engine oil pan on a Ford F350 and with using Amsoil the pan inside was 100% clean, zero deposits. A larger oil pan was installed, no engine problems.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil
    By  DOUGLAS,  a  Verified Buyer  on  December 05, 2022
    Don't waste your money on cheap oil, in the end you will save money.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil
    By  PAUL,  a  Verified Buyer  from  Moses Lake   on  November 28, 2022
    It's a great product and a good value.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel Oil
    By  TED,  a  Verified Buyer  from  Montana  on  October 25, 2022
    Oil performs excellent. Starts good in cold weather and motor runs smooth. Highly recommended.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Low Temp Oil
    By  DAVE,  a  Verified Buyer  from  Big Valley AB Canada  on  October 15, 2022
    This oil is amazing at our subzero temps in the winter and lubes great through the summer.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent
    By  BRYON,  a  Verified Buyer  from  Tooele, Utah  on  September 15, 2022
    Excellent oil for my truck.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The only oil I will use in my diesel truck
    By  Augie,  a  Verified Buyer  from  MN  on  August 25, 2022
    This is great oil and a good price it's the only oil I will put in my diesel truck
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil
    By  MICHAEL,  a  Verified Buyer  on  August 14, 2022
    I decided to go with Amsoil I was introduced to it in the 80’s it was expensive back then so I went with Mobil1 had know issues with Mobil1 but there’s a big difference I can see already been in my Dodge Ram for three weeks now and it is still clear to the eye. Mobil1 would definitely be black by now. All I’m saying is Amsoil has made a believer out of me. I got the differential oil so that’s my next change. Good stuff will recommend
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome oil
    By  Doug,  a  Verified Buyer  from  Leduc  on  August 05, 2022
    Great Product Awesome service
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    5-40 diesel oil
    By  BRENT,  a  Verified Buyer  from  Black hills So Dak  on  August 04, 2022
    Great product I own a 6.4 powerstroke and I switched from conventional non synthetic oil to amsoil and the tic stopped! Highly recommended
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    To early to tell
    By  KEVIN,  a  Verified Buyer  on  June 03, 2022
    After hearing all the hype I decided to give amsoil a shot. I drive a 2015 F-350 6.7 powerstroke. I was a little disappointed To hear the dreaded typewriter tick as soon as I fired it up. I’ll run it for a while and change it again and see how it does on the second oil change. So Far I’m happy with it, the way it was shipped left a lot to be desired though. The box it came in had arrows saying this side up and both 2.5 gallon jugs were packaged upside down on their caps. They also forgot the free gift I was supposed to get which was like pulling teeth to get a replacement sent out.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    great product
    By  DONNIE,  a  Verified Buyer  from  GA  on  May 31, 2022
    it works
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Oil
    By  DAVID,  a  Verified Buyer  on  May 30, 2022
    Just put this in my John Deere 1025R sub compact tractor. Sound better and runs smoother. When I first fired up the tractor after the oil change, i could not believe how much smoother the tractor run at idle and all the way up to full throttle. At this point in time, I'll never use another oil in this tractor. Great stuff.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product
    By  CHARLES,  a  Verified Buyer  on  May 27, 2022
    I actually use this in a 07 Canyon and 14 Outback. The canyon burns 5w30 but not this. The outback burned a quart every 1000 miles of the 0w20, switched to 0w40 and burns a quart every 4000, I’ll try this in it and see. Next step will be 5w50. Outback is just a complete pos.
    Bottom Line
    Yes, I would recommend this to a friend.
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