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SAE 15W-40 Heavy-Duty Diesel and Marine Oil

Product code : AMEQT-EA

4.9 star rating
Read 257 reviews
Read 257 reviews

  • Recommended for applications specifying API CI-4+ and prior specifications
  • Controls soot and wear
  • Reduces oil consumption and emissions
  • Delivers maximum engine protection over extended drain intervals
  • Provides outstanding protection and performance in temperature extremes
  • Try Signature Series Max-Duty 15W-40 for a serious upgrade

Warning - Click here for Proposition 65 information for this product
Product Overview

SAE 15W-40 Heavy-Duty Diesel and Marine Oil



Premium diesel oil providing excellent performance in diesel engines where highly effective control of wear and deposits is vital. Built with heavy-duty dispersant/detergent additives with 12 TBN, Synthetic Heavy-Duty Diesel & Marine Oil neutralizes acids and controls soot thickening from EGR and blow-by to protect against corrosion, cylinder bore polishing (wear) and varnish/sludge deposits. It resists heat and breakdown and is formulated for extended drain intervals.

See the product data sheet for full details.

CONTROLS SOOT AND WEAR

  • Neutralizes acids and controls soot thickening to protect against corrosion, wear, varnish and sludge deposits
  • Reduces oil consumption and emissions
  • Delivers maximum engine protection over extended drain intervals

EXCELS IN EXTREME TEMPERATURES

  • Provides outstanding protection and performance in temperature extremes
  • Resists heat and breakdown better than conventional oils
  • Eases cold-weather starting and provides vital startup lubrication

 

See the product data sheet for full details.

Technical Specification

SAE 15W-40 Heavy-Duty Diesel and Marine Oil

Data Bulletin

Warranty

SDS



Product Reviews

SAE 15W-40 Heavy-Duty Diesel and Marine Oil

4.9 star rating
Based on 257 reviews
Based on 257 reviews
See all customer reviews
  • 5 star rating
    AMS oil purchase
    By  RAY,  a  Verified Buyer  from  Oklahoma  on  November 27, 2023
    In my opinion this is the best oil product available.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Running hard
    By  PAL,  a  Verified Buyer  from  Ontario  on  October 12, 2023
    It can be -42F winter in northern Ontario or 110F summer in south Texas. I am running this oil in my CAT 3406E since 2006. Changing it at 60K miles. Engine has 3 million miles on and it was rebuilt once since 1996. DO I HAVE TO SAY MORE? Thank you Amsoil!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 4 star rating
    Marine Diesel Oil
    By  GREGORY,  a  Verified Buyer  from  Chicago  on  October 11, 2023
    Great oil but it has gotten very expensive.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Walter
    By  YAREMCHUK,  a  Verified Buyer  on  September 01, 2023
    Very good quality
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Holds Up
    By  CSTX77,  a  Verified Buyer  from  San Antonio, Texas  on  August 23, 2023
    Oil really holds up in the heat and tough conditions. At regular oil change still feels like it has good viscosity and some life left
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    The only oil I’ll run in my Ford 7.3!
    By  JEREMY,  a  Verified Buyer  from  South Dakota  on  August 12, 2023
    The only oil I’ll run in my Ford 7.3!
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Marine HD 15W-40
    By  ERIC,  a  Verified Buyer  from  Moncton N,B  on  July 15, 2023
    Using this diesel motor oil in a J-D Yanmar skid steer 7775 since new (1999) Amsoil is the best!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good stuff
    By  BRAD,  a  Verified Buyer  from  Tennessee   on  June 13, 2023
    Well packaged and quality
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Quick delivery
    By  DAVE,  a  Verified Buyer  from  Kelowna BC  on  May 09, 2023
    The delivery was vey quick. Unfortunately this product has been discontinued because it was ideal for my vehicle which requires at least 3000 ppm calcium detergent. Hopefully one of your other products meets this specifications.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    my summer oil
    By  FRANK,  a  Verified Buyer  from  Montana  on  April 06, 2023
    I use this oil for the summer months. I'm happy with it.
    Was this review helpful?