DELO SILVER EXTRA (20W-50)-4L is a high-performance heavy-duty diesel engine oil designed for engines requiring API CH-4/SJ lubricants and higher-viscosity protection. Its advanced formulation ensures excellent engine cleanliness, strong soot dispersancy, and superior oxidation stability to reduce maintenance costs. With proven anti-wear additives and robust multigrade protection, it extends engine life, preserves power, and performs reliably in mixed fleets, commercial transport, off-highway equipment, agriculture, and marine diesel engines.