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AMSOIL Signature Series 5W-40 100% Synthetic Max-Duty Diesel Oil

Product code : DEOQT-EA

4.9 star rating Read 1,156 reviews

Customer Rating

4.9

91% would recommend

  • 5 1103
  • 4 40
  • 3 4
  • 2 3
  • 1 6

AMSOIL Signature Series 5W-40 100% Synthetic Max-Duty Diesel Oil

4.9 star rating Based on 1,156 reviews
  • 5 star rating
    Does the job well
    By  NATHAN,  a  Verified Buyer  on  July 29, 2023
    Switched from royal purple to this because the LB7 would not hold oil pressure when it was hot and it was burning oil and it never did before using the purple. Truck now holds oil press at 30 at idle when hot and is back to not using oil. Will not use anything else in this truck now
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Only the best!
    By  ANDREW,  a  Verified Buyer  from  Lebanon, IN  on  July 27, 2023
    This product has the best anti-wear properties offered by any manufacturer. The 2.5gal jug is exactly what my vehicle requires. Customer support is amazing. The wide range of products offered by Amsoil makes them a one stop shop for any internal combustion engine you may have. I highly recommend Amsoil for your next and future needs!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Really great product.
    By  DALLAS,  a  Verified Buyer  from  Phoenix AZ  on  July 18, 2023
    I have a 2019 and 2023 Duramax and I always use Amsoil it both. The oil pressure and temp stay very consistent doesn’t matter if it is fresh or at 8,000 miles.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    100,000 miles and runs and sounds like the day I bought it
    By  PHIL,  a  Verified Buyer  from  FL  on  July 18, 2023
    First truck I have used it in. The ram 2500 diesel to expensive to put cheap oil in. Very happy with it my oil pressure is a little lower and I change it every 15000 per Cummins. Oil is as clean (particule wise as the first day) Only the best for my truck.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Seems to work well
    By  REASE,  a  Verified Buyer  from  Bonita Springs,Florida   on  July 16, 2023
    Use 15-40 synthetic diesel oil also in differential
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good product
    By  CESAR,  a  Verified Buyer  from  Orlando   on  July 11, 2023
    use amsoil for all your equipment don't risk it with cheap oils.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Simple the best
    By  JEFFREY,  a  Verified Buyer  from  Ft. Lauderdale   on  July 08, 2023
    It’s the only oil I use in my Diesel truck and motorcycle, Go with the best do your oil changes , it’s the cheapest way to keep anything from happening!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The best oil
    By  JOE A,  a  Verified Buyer  from  Hollywood, FL  on  July 07, 2023
    I have been using this oil for some time now and find it to be the best lubricant for my diesel truck. Everything runs smoothly and quiet.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome Oil!
    By  ANDREW,  a  Verified Buyer  from  Pennsylvania   on  July 02, 2023
    Oil used in 6.4 hemi and 6.2 gmc. Works very well.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Outstanding performance
    By  PAM,  a  Verified Buyer  from  Vermont  on  June 28, 2023
    We are off grid and have a diesel generator. I have used only Amsoil products for this essential equipment. Still humming after 7years of service.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Everywhere
    By  CHARLIE,  a  Verified Buyer  from  Louisiana   on  June 26, 2023
    I have a small horse farm. We use Amsoil Max duty 15w-40 in both tractors, both diesel trucks for long life and protection.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    My 6.0 loves it!!
    By  MICHAEL,  a  Verified Buyer  from  So Cal  on  June 25, 2023
    Ordered before noon and recieved the next day!! My 6.0 loves this stuff. Extremely happy with this oil!! Will continue to recommend to others.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil
    By  RICHARD,  a  Verified Buyer  from  Alberta Canada   on  June 25, 2023
    I use this in my 2 diesel trucks and my welding machine
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good
    By  RAMON,  a  Verified Buyer  from  Houston   on  June 23, 2023
    Best motor oil
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel
    By  KEVIN,  a  Verified Buyer  from  Maryland   on  June 20, 2023
    Quick service , received oil in two working days . Been using since I purchased my vehicle with no issues . Thanks AMSOIL ..
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    Product good, customer service?
    By  DAVID,  a  Verified Buyer  from  Olympia wa  on  June 15, 2023
    After I order I received no confirmation email or updates on delivery date. Felt lucky when the order arrived. A bit more communication could go a long way. Like look at the successful online stores maybe.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The Best Oil Period!
    By  TRENT,  a  Verified Buyer  from  Hernando, MS  on  June 15, 2023
    I really can tell a difference using this oil vs any other on my 6.7 Powerstroke. It really runs very smooth. All I'll ever use for oil in my diesel. Very happy.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great engine product
    By  TIMOTHY,  a  Verified Buyer  on  June 14, 2023
    This product meets or exceed any diesel oil product out there! The only engine oil I will ever use in my truck period
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good Oil
    By  CLINT,  a  Verified Buyer  from  Tennessee   on  June 11, 2023
    I have a 2016 Silverado 2500hd LML. When I purchased the truck it had 120,000 miles on it. I have used this product since the first full service that I did on the truck. I change the oil every 5000 miles it runs quit and smooth. Although it is pricey I will remain using it
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Consent product
    By  NATHAN,  a  Verified Buyer  on  June 07, 2023
    Very consent product. I know when a purchase this oil I'm getting a great product every time.
    Bottom Line
    Yes, I would recommend this to a friend.
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