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Customer Ratings & Reviews

Heavy-Duty Synthetic Diesel Oil 5W-40

Product code : ADOQT-EA

4.9 star rating Read 53 reviews

Customer Rating

4.9

100% would recommend

  • 5 50
  • 4 3
  • 3 0
  • 2 0
  • 1 0

Heavy-Duty Synthetic Diesel Oil 5W-40

4.9 star rating Based on 53 reviews
  • 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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  • 5 star rating
    Reliably Refreshing
    By  CHARLES,  a  Verified Buyer  from  Texas  on  May 24, 2022
    In these truly challenging times it is a joy to find reliability in vendors. Many local vendors were out of oil for my diesel truck, I’m sure they are doing all they can to help their customers. A friend suggested Amsoil and I got a pleasant surprise. Amsoil seemingly has no logistical issues or they are managing them well and providing a great product for consumers. I highly recommend Amsoil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    08 Dodge Ram 3500 mega cab
    By  MICHAEL,  a  Verified Buyer  from  Arizona  on  May 20, 2022
    Looking forward to see how this oil compares to Rotella’s full synthetic 5W40.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product
    By  PATRICK,  a  Verified Buyer  on  May 19, 2022
    Trucks runs smoother and quieter
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent oil. Ordering and delivery was a breeze
    By  FAWNA,  a  Verified Buyer  on  April 24, 2022
    I am very impressed with the oil and customer service ♡
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Outstanding service and user interface
    By  Tony,  a  Verified Buyer  from  Houston, Tx  on  April 20, 2022
    Did a lot of research so that I could make sure that I would get the best oil for my ecodiesel. The detergent and additives package in Amsoil oil met and exceeded all my needs. The user interface on the website was fantastic, clearly and concisely helping me pick the right product for my truck and suggesting the filter that I would need. Shipping was super fast and arrived just as described and well packaged. Would definitely and have suggested to friends and co workers.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  ADAM,  a  Verified Buyer  on  April 17, 2022
    Love this oil. Runs good in my superduty.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    No comparison
    By  MATTHEW,  a  Verified Buyer  on  March 25, 2022
    Used amsoil for years in most of my vehicles. Just started using it in my semi and have seen a decrease in oil consumption.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great service, fast delivery
    By  JMiller,  a  Verified Buyer  from  Waverly, Ohio   on  March 24, 2022
    Amsoil has always had top notch products. The shipping time is amazing. Ordered and received my oil the next day
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    I use the Heavy-Duty Synthetic Diesel Oil in everything
    By  CURTIS,  a  Verified Buyer  from  Tuscola, Texas  on  March 23, 2022
    My go-to oil for any application has been the Heavy-Duty Synthetic Diesel Oil in the 5W-30 weight by and large. Most of the actual diesel equipment use the 5W-40 weight.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil
    By  MICKY,  a  Verified Buyer  from  Coldspring TX  on  March 22, 2022
    Na
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil Diesel Oil
    By  ROBERT,  a  Verified Buyer  on  March 20, 2022
    Excellent diesel oil and I run it in my F250. I will continue to use Amsoil over Rotella oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome
    By  DOUGLAS,  a  Verified Buyer  on  February 25, 2022
    Using oil tests on my engine this oil worked Great!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product
    By  STEVEN,  a  Verified Buyer  on  February 17, 2022
    Great product will definitely get again & good price as well
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    5-40 HD Diesel oil
    By  STEVE,  a  Verified Buyer  from  PA  on  February 16, 2022
    I use Amsoil in all of my Vehicles. The quality and price is hard to beat, especially if you have the membership. Definitely recommend.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Ram Eco-Diesel
    By  PHIL,  a  Verified Buyer  on  February 15, 2022
    Great product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil Diesel
    By  LOUIE,  a  Verified Buyer  from  Minnesota  on  February 14, 2022
    I've had the same truck and used the same oil and filter for nearly 10 years now. This is a 25,000 mile filter and I change every 2 years with roughly 7,000 on the change. No issues, no oil use, not knocking, no cold weather starting issues and no smoking. I call that a win and will keep this combo going as long as I own the truck. I did take one step down from the Amsoil Signature to the HD Turbo oil but I do not anticipate any problems with that change.
    Bottom Line
    Yes, I would recommend this to a friend.
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