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

Product code : AMEQT-EA

4.9 star rating
Read 267 reviews
Read 267 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

AMSOIL 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

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

Data Bulletin

Warranty

SDS



Product Reviews

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

4.9 star rating
Based on 267 reviews
Based on 267 reviews
See all customer reviews
  • 5 star rating
    Oldtimer
    By  PAL,  a  Verified Buyer  from  Windsor, ON  on  July 05, 2024
    I am running with this oil since 2007. Caterpillar 3406E. Oil changes are way over 60K miles. Do I need to say more?
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great Stuff
    By  DAKOTA,  a  Verified Buyer  from  Arkansas  on  June 05, 2024
    Have always ran Rotella or the Polaris brand oil in our Polaris Ranger Diesel. Made the switch and immediately the motor is far quieter than it has ever been. Seems to stay cleaner as well
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    15w40 diesel marine oil
    By  STEVE,  a  Verified Buyer  on  April 29, 2024
    Best oil you can buy.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Diesel and Marine
    By  KEITH,  a  Verified Buyer  from  desert southwest  on  April 25, 2024
    I have been using this oil in my Ford 7.3 for 15 yrs without a single problem. I change oil and filter every 10,000mi.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Walter
    By  YAREMCHUK,  a  Verified Buyer  on  April 16, 2024
    Very good quality
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Synthetic 15w40 diesel oil
    By  DAVID,  a  Verified Buyer  from  Ocala FL   on  March 03, 2024
    Good price excellent product
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    15/40 HD diesel oil
    By  KEVIN,  a  Verified Buyer  on  January 29, 2024
    My 04 , 5.9 cummins loves this stuff.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Oil
    By  JEFFREY,  a  Verified Buyer  from  Personal  on  January 16, 2024
    Excellent Oil. Have used it for years in my Duramax
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Walter
    By  YAREMCHUK,  a  Verified Buyer  on  December 05, 2023
    Very good quality.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 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?