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Diesel Gard 15W-40 CJ-4/SM


Duckhams Diesel Gard 15W-40 CJ-4/SM is a top tier multi-grade diesel engine oil for heavy-duty diesel engines. Formulated using modern additive technology and high-quality virgin base oils to meet current specifications and provide advanced protection for all vehicles operating under severe conditions.

Duckhams Diesel Gard 15W-40 CJ-4/SM is a premium quality engine oil formulated using modern additive technology to provide advanced engine protection for modern low emission, and older high speed four stroke diesel engines. It has been designed to provide excellent protection against wear and corrosion, even when operating under sever conditions, whilst still protecting exhaust after treatment systems and minimising emissions.


  • Low ash formulation designed to work with low emission engines, including those fitted with Exhaust Gas Recirculation (EGR), Particulate Filters (PFs) and Selective Catalytic Reduction (SCR) systems.
  • Suitable for use in both older and modern low emission on-highway vehicles and off-highway equipment operating in severe operating conditions.
  • When used with ultra-low sulphur (15ppm) diesel fuels, gives extended oil drain interval. Can also be used with low sulphur (500ppm) diesel fuel. Always check your vehicle handbook.
  • Formulated with detergent and dispersant additives which provide excellent soot handling, minimising soot related viscosity increases, and reducing abrasive wear, increasing engine life whilst also providing exceptional base number control, protecting against the formation of harmful acids, reducing corrosion and extending oil life.
  • Outstanding thermal and oxidative stability reduces low-temperature sludge formation, high temperature deposit build-up and oil thickening, maintaining engine cleanliness and performance.
  • Formulated to be suitable for use in all naturally aspirated, or turbo charged, four stroke diesel or gasoline engines where an SAE 15W-40 oil, meeting API CJ-4 or API SM is required, also backward compatible with API CI-4+, CI-4, CH-4 and API SM, SL and SJ performance levels.