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DURAFLOW Heavy Duty CJ-4/SN 15W-40 Diesel Engine Oil features:

  • Premium performance additives blended in high quality API group II conventional base oils that allows for use in severe service conditions with diesel fuel containing high or low amounts of sulfur.
  • Formal API CJ-4/SN license.
  • Safe for use with modern exhaust after treatment systems that were initiated in 2007 and 2010 such as diesel particulate filters, exhaust gas recirculation, diesel oxidation catalysts, and selective catalytic reduction systems.
  • A robust, all calcium based, detergent package designed to neutralize and suspend high amounts of acidic combustion byproducts during service.
  • Meeting the CJ-4 diesel specifications, this product can be considered “backwards compatible” to older API diesel engine oil specifications such as CI-4 PLUS, CI-4, and CH-4.