ProFleet IS 10W-40 is a full synthetic heavy duty diesel engine oil meeting the API CK-4 specification. Formulated for use in diesel engines in trucks, buses and industrial equipment requiring a lower Sulphated Ash, Phosphorus and Sulphur (SAPS) content to protect after treatment systems such as Exhaust Gas Recirculation (EGR), Selective Catalytic Reduction (SCR) systems and Diesel Particle Filters (DPF) after treatment systems.