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

Product code : DMEQT-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
    Works great
    By  VINCE,  a  Verified Buyer  from  Louisiana  on  March 08, 2021
    Engine seems like it better than whatever was in it before. Dropped my oil pressure a little bit, but it was my first oil change after buying truck used so I don’t know what was in it before. I’ll continue using Amsoil products for the life of my diesel.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  GREG,  a  Verified Buyer  from  Fontana ca  on  March 07, 2021
    I’ve been using Amsoil in all my trucks for 12 years Awesome Products and very Fast Service
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 3 star rating
    Customer service
    By  TONY,  a  Verified Buyer  from  Kirbyville Texas  on  March 03, 2021
    I want to start by saying the customer service was very excellent they knew everything about the product I was ordering!!! and very swift shipping I had my oil in two days unbelievable thank you !!!! I would love to write a review on how the oil 15 W 40 max duty signature series full synthetic is holding up in my new high-performance 6.7 L diesel is performing !!!!!but of course with the hard freeze and pandemic my mechanic is very busy ,as soon as my old motor is Pulled out and my new high-performance motor in.. I have a 800 mile break in. After that I will have the oil tested !!! and right another review !!!15 W 40 synthetic Max duty signature series. Thank y’all at AMSOIL. Look forward to yawls business for many years. Please pay no mind to the 5 Star rating it will not let me post unless I rate it I know for a fact that it is a very good oil I have not run it yet Or tested it in my new high-performance motor!!! Like I said earlier in my review I will write another after I hit run and tested it
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Buy it Use it
    By  STEVE,  a  Verified Buyer  from  Little Rock ,AR  on  March 02, 2021
    I run this in my 97 Dodge 12 valve Cummins 190K and it runs smooth as silk , hauled a 33'camper from Little Rock to Grand Junction ,CO Feb 2020 and it purred right through the Rockies zero problems . I suggest it to everyone I can .
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  TODD,  a  Verified Buyer  on  March 02, 2021
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  MATHEW,  a  Verified Buyer  from  Bloomington, MN  on  March 02, 2021
    Great oil for all weather applications
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best Oil
    By  LEROY,  a  Verified Buyer  from  Florida  on  February 26, 2021
    Reviewed the test results and I am satisfied the oil suits my needs. I do some heavy hauling and have used the oil since the truck was new. No issues.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil
    By  RYAN,  a  Verified Buyer  from  Florida   on  February 25, 2021
    Love amsoil the only oil I run in my diesel truck
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  TODD,  a  Verified Buyer  on  February 24, 2021
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  ADAM,  a  Verified Buyer  on  February 23, 2021
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Difference you can here
    By  STEPHEN,  a  Verified Buyer  on  February 23, 2021
    I was running another big name brand (T6) synthetic oil before, after switching to AMS oil I can here a difference in how the motor idles. Much smoother and quieter than before
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil
    By  ALEC,  a  Verified Buyer  from  LA County   on  February 23, 2021
    Not much to say other then best oil on the market. I don’t use anything else. I use this in my 2001 Chevy Duramax that is always towing. 10/10 recommend
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    GREAT PRODUCT / CUSTOMER SERVICE
    By  JAMES,  a  Verified Buyer  from  NORTH CAROLINA  on  February 21, 2021
    GREAT PRODUCT BEEN USING FOR YEARS WITH NO ISSUES, CUSTOMER SERVICE ALSO RECEPTIVE TO REQUESTS. I FEEL LIKE I KNOW THEM PERSONALLY
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  MICHAEL,  a  Verified Buyer  from  Syracuse,NY  on  February 19, 2021
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    #1
    By  HAROLD,  a  Verified Buyer  on  February 18, 2021
    I drive my diesel approx 4000 plus miles a week. Amsoil is without a doubt the best full synthetic oil and 2nd to none
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    315,000 mi
    By  STEVEN,  a  Verified Buyer  from  Mass  on  February 17, 2021
    I've used this oil for years on my truck Duramax diesel 315,000 And the motors never been opened it's all I have to say
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  VINCENT,  a  Verified Buyer  on  February 17, 2021
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Diesel oil
    By  MARK,  a  Verified Buyer  from  Iowa  on  February 15, 2021
    This oil I have been using ever since I got involved Amsoil I can’t tell you what the inside of the motor looks like because I’ve never had her taken one apart I had a Ford truck for the diesel Dodge Cummings now running it on 2014 Jeep Cherokee Limited and I never have had a problem with it I live in Iowa right now it’s 13 below zero and a cranks over like summer time.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    By  GALEN,  a  Verified Buyer  on  February 14, 2021
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The product I was looking for!
    By  LAYTON,  a  Verified Buyer  from  Beeville Texas   on  February 13, 2021
    So I’ve bought high end oils before like certified Labs and lubrication engineers Amsoil has surpassed those “competitors” I put this in quotations cause they truly don’t compare.
    Bottom Line
    Yes, I would recommend this to a friend.
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