Frankol 15W40 CK-4/SN Semi Synthetic oils are prepared for both diesel engine and gasoline engines. The fine viscosity at low temperatures boosts efficiency even at cold start. These are capable of working smoothly even in harsh conditions thus magnanimously prolonging oil and engine life. The Frankol 15W40 CK-4/SN Semi Synthetic oils are efficient in preventing soot deposits and strengthening equipment horsepower thus making the engine more durable. These exponentially enhance oil mileage and improve viscosity stability to reduce oxidative thickening.