Coolant replacement refers to completely draining the old coolant from the vehicle's cooling system and replacing it with new coolant to ensure the engine's heat dissipation system operates efficiently. When performing the operation, ensure the engine is fully cooled, typically requiring at least 4 hours after shutdown to avoid burns from high-temperature fluid splashes. The specific steps include: opening the engine compartment to locate the coolant reservoir, draining the old fluid and cleaning the lines, then refilling with new coolant meeting OEM specifications up to the MAX mark, starting the engine to idle for air bleeding, and finally verifying the fluid level is within the normal range. For instance, conventional green/blue coolant requires replacement every 2 years, while red Organic Acid Technology (OAT) coolant can last up to 5 years - mixing them causes chemical degradation. For high-mileage vehicles (e.g., exceeding 30,000 km) or those with prolonged overdue replacement, it's advisable to concurrently inspect cooling lines for cracks or leaks. Luxury vehicles with complex structures should be serviced by professional technicians. Regular replacement effectively prevents engine overheating and radiator corrosion. Refer to the maintenance manual for specific intervals, typically 2 years or 40,000 km (whichever occurs first).
