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AMSOIL Signature Series 15W-40 100% Synthetic Max-Duty Diesel Oil

Product code : DMEQTC-EA

4.9 star rating Read 1,550 reviews

Customer Rating

4.9

92% would recommend

  • 5 1485
  • 4 45
  • 3 9
  • 2 3
  • 1 8

AMSOIL Signature Series 15W-40 100% Synthetic Max-Duty Diesel Oil

4.9 star rating Based on 1,550 reviews
  • 5 star rating
    Great oil that lasts a long time
    By  BOBBYG09,  a  Verified Buyer  from  Bandera  on  December 31, 2020
    So I’ve been a long time AMS fan but just recently I just sent off oil analysis on both of my diesel trucks. One being an OBS 7.3, and the other being common rail 5.9. Both having well over 350xxx miles on the clock. That that being said the oil analysis came back absolutely perfect with the amount of miles The recommended by the manufacturer to be changed. The TBN was also perfect and Blackstone recommended that I go even longer on my next oil change. This oil isn’t snake oil. It really is fantastic oil that not only does what it says but costs as much or LESS then your parts store oils you get. Of course you want to get it directly through AMSOIL for all their deals. Other then that, I’m set to keep buying my oil from AMSOIL. Thanks guys
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  BRYAN,  a  Verified Buyer  from  Michigan  on  December 30, 2020
    I really like the Amsoil oil products & have been using them in my work trucks & cars since 2005.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Smoother quieter cooler
    By  FRED,  a  Verified Buyer  from  Pennsylvania   on  December 29, 2020
    Outstanding product our 5.7 Hemi Challenger runs stronger, quieter, smoother and cooler. We plan on using this oil for a very long time
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  DOUG,  a  Verified Buyer  on  December 29, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  MICHAEL,  a  Verified Buyer  from  Menifee. California   on  December 25, 2020
    There is no better oil for prolonged use, especially in conjunction with the Amsoil bypass filter. I just change the 20 micron filter every 8000 miles, and the oil at 24000, or sometimes more
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Duramax oil
    By  REG,  a  Verified Buyer  from  Parksville BC  on  December 25, 2020
    Great product- Best protection and extended oil change- once a year!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great
    By  ALEXANDER,  a  Verified Buyer  from  North Dakota  on  December 24, 2020
    I’ve used this product in a 6.0L powerstroke where it made the truck run smooth as could be. Allowed me to extend my drain intervals, as I ran OTR with it and was doing 10k miles a month. I currently use it in my 6.7L powestroke where it does a phenomenal job with all the idling and towing. Being in North Dakota I love the cold weather protection!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  Mike ,  a  Verified Buyer  from  The Desert   on  December 23, 2020
    Best diesel oil I can find!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil
    By  MARK,  a  Verified Buyer  on  December 23, 2020
    I have been using amsoil in my 2008 F250 powerstroke for years and with 220k on the engine with a tuner. Engine still doesn't burn oil after all this time. Great product and will continue to recommend it to others.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 1 star rating
    By  JOEY,  a  Verified Buyer  on  December 23, 2020
    Not a true quart of oil first off. Secondly in the L5P Duramax This oil creates the type writer tick. The Mobile1 I was running didn’t. Not impressed with the over priced oil that doesn’t seem to do it job regardless of what they claim.
    Bottom Line
    No, I would not recommend this to a friend.
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  • 5 star rating
    By  THEO,  a  Verified Buyer  on  December 21, 2020
    I have used Amsoil products for years with great success, putting hundreds of thousands of Km of trouble-free driving with no oil consumption or any evidence of wear
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Top Quality Oil
    By  Lynn,  a  Verified Buyer  from  Sherwood Park  on  December 20, 2020
    For many years I have been using Amsoil Synthetic 5W40 SS Diesel Oil in all of my Equipment, Trucks and Cars. I use it in both diesel and gas engines. I like the long intervals between oil changes. Some of my engines are old. They are lasting a long time and are keeping clean inside. I use this oil in both winter and summer. My car does not have a block heater and it will start in temperatures of -30 C.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Awesome engine oil
    By  ED,  a  Verified Buyer  from  San Diego  on  December 17, 2020
    I am a mechanical engineer with 36 years experience and will use nothing but Amsoil products in my vehicles. If you want to keep your engines running for a long time you want the best lubricating oil possible. All tests reveal Amsoil synthetic oil and filters are the best. Even performance shops like Banks Power recommends Amsoil products!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil Diesel Oil is the best oil for my 12 valve Cummins
    By  TIMOTHY,  a  Verified Buyer  from  Northern California   on  December 15, 2020
    I’ve tried others but none performed as well as Amsoil in my 12 valve Cummins. The truck has 265k miles on it and Amsoil stays clean longer and reduces oil consumption over the oil change interval.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil in the world
    By  JUAN,  a  Verified Buyer  from  Fl  on  December 14, 2020
    I have been using this oil for 3 years and I love it no problem the motor sounds different and performs better.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  JOHN,  a  Verified Buyer  from  Gainesville Texas  on  December 14, 2020
    I just started traveling full time pulling a 5th wheel. I wanted to use a good oil so in my research determined Amsoil was one of the best Synthetic Oils I could buy. So I’m giving it a try. My truck has 212,000 miles and I’ve had no problems but with those miles I wanted something better than average to protect my engine so I went with the Amsoil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Excellent products
    By  JESSE,  a  Verified Buyer  from  California   on  December 13, 2020
    Amsoil definitely makes the best oil on the market and has the test data to prove it. I use their oil, filters and fuel additives in both my vehicles. Their diesel fuel additive cut the regen frequency by more than half on my 2020 duramax. Highly recommend all amsoil products.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel Oil
    By  STEVE,  a  Verified Buyer  from  Utah  on  December 12, 2020
    Works very well, used to use a different Amsoil product switched to this for the added wear protection and the extended drain intervals
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oils and fast delivery
    By  TRENT,  a  Verified Buyer  from  Grande Prairie AB  on  December 09, 2020
    This is the only product I use in my super duty 6.7L
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 4 star rating
    By  JEFF,  a  Verified Buyer  from  Leander, Texas  on  December 06, 2020
    Bottom Line
    Yes, I would recommend this to a friend.
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