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

  • 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

Product Overview

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.

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

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Product information checked: September 2026. Product formulations, specifications, applications, availability and published claims can change.
For the latest official information, consult the AMSOIL Corproate Website.

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