Main Menu

Delivery may take 5-7 days due to high seasonal demand.

Customer Ratings & Reviews

Signature Series Max-Duty Synthetic Diesel Oil 5W-40

Product code : DEOQT-EA

4.9 Read 418 reviews

Customer Rating

4.9

79% would recommend

  • 5 396
  • 4 18
  • 3 1
  • 2 1
  • 1 2

Signature Series Max-Duty Synthetic Diesel Oil 5W-40

4.9 Based on 418 reviews
  • 5
    By  ERNESTO,  a  Verified Buyer  from  Hialeah / Florida  on  November 25, 2020

    Describe the issue

    The oil I requested for my 2014 Ram/ 6.7 was delivered on time and well packed with no damage . This is the second time I’ve purchased from AMSOIL and will continue in the future . Highly recommend them !
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  BRIAN,  a  Verified Buyer  on  November 22, 2020

    Describe the issue

    The product speaks for itself
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  CHASE,  a  Verified Buyer  on  November 21, 2020

    Describe the issue

    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Dodge Cummins
    By  GEORGE,  a  Verified Buyer  from  Nc  on  November 19, 2020

    Describe the issue

    I was fortunate to grow up around Amsoil and the benefits of using it I wouldn't use anything else it's the best oil hands down!
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    amsol signature-series-max-duty-synthetic
    By  DENNIS,  a  Verified Buyer  from  Wi  on  November 19, 2020

    Describe the issue

    This 5w40 diesel oil have great protective qualities, and actually made my diesel motor quieter. Due to superior lubrication.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Quiet confidence
    By  CHRIS,  a  Verified Buyer  from  MD  on  November 17, 2020

    Describe the issue

    My 2014 Ram Eco Diesel hums with Amsoil. I have gained in gas mileage and my truck warms up quicker. Love this product - it’s worth the extra $ - invest in your vehicle.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  MIKE,  a  Verified Buyer  on  November 16, 2020

    Describe the issue

    Great oil doesn’t break down
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  EDGAR,  a  Verified Buyer  on  November 14, 2020

    Describe the issue

    I’m just going to keep it simple,your not going to find nothing better then this......Amsoil #1
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  Dennis,  a  Verified Buyer  from  Dawson Creek  on  November 13, 2020

    Describe the issue

    My son uses it in his 2004 dodge truck. Highly recamends it.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  DOUGLAS,  a  Verified Buyer  from  Kentucky  on  November 12, 2020

    Describe the issue

    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    excellent oil life
    By  Aaron,  a  Verified Buyer  from  West Virginia  on  November 11, 2020

    Describe the issue

    I use this in my 97 Dodge 2500 12 valve cummins, and my 2006 F450 6.0 powerstroke. I never have to add oil to either one between oil changes. No issues using this oil.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Dodge trucks
    By  Anonymous,  a  Verified Buyer  from  Yantis Texas   on  November 07, 2020

    Describe the issue

    My son has run it in his dodge diesel for several years does a great job. I run a amsoil in both of our vehicles for many years won’t run anything else.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Clean difference
    By  G,  a  Verified Buyer  from  South Florida  on  November 07, 2020

    Describe the issue

    Switched to Amsoil this year. I can tell from my services the oil is a night and day difference as far as it’s clarity compared to Rotella Sythetic. Both oils ran with a 2 micron Amsoil by pass filter. I have been replacing the 2 micron filter every other oil service regardless. Just installed a BANKS wet filter CAI. Interested in seeing if there is any change to the next oil service.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    15W40 Diesel Engine Oil
    By  Anonymous,  a  Verified Buyer  from  Seattle Wa  on  November 05, 2020

    Describe the issue

    Running this in my 98 Cummins 12valve using Donaldson filter and got 16,000 miles with oil still able to go a bit further. That's towing a 14,000lb 5th wheel for at least half that mileage. Also I lost less oil to evaporation from engine temps towing when I switched from Rotella T6, plus Amsoil doesnt have the french fry smell that Rotella T6 does. Only negative is initial cost, but its more than made up for in time between oil changes.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    Great product
    By  Tom,  a  Verified Buyer  from  Nebraska  on  November 05, 2020

    Describe the issue

    I have used this oil in all my diesel engines. Including Deere tractors, and duramax pickups. Zero problems in my almost 15 year old engines.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 4
    Needs a little work to be perfect
    By  Keith ,  a  Verified Buyer  from  Maine   on  November 04, 2020

    Describe the issue

    This 17 lb jug is really handy, however a pour spout with flexible neck like the one used for DEF Fluid would seal the deal on this all in one 10 qt jug.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By far the best
    By  Dave ,  a  Verified Buyer  from  Oklahoma   on  October 29, 2020

    Describe the issue

    Amsoil is the best oil you can get there’s nothing better. If you want your vehicle to last get Amsoil and don’t look back.
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    tractor oil
    By  larry,  a  Verified Buyer  from  43944  on  October 29, 2020

    Describe the issue

    tractor runs quieter with this oil
    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  Anonymous,  a  Verified Buyer  on  October 28, 2020

    Describe the issue

    Bottom Line
    Yes, I would recommend this to a friend.
  • 5
    By  Anonymous,  a  Verified Buyer  on  October 28, 2020

    Describe the issue

    Bottom Line
    Yes, I would recommend this to a friend.