The maintenance of coolant should involve choosing between cleaning and replacement based on the vehicle's usage conditions and the quality of the antifreeze; these two are not mutually exclusive but complementary maintenance measures. For conventional ethylene glycol-based antifreeze, a complete replacement is recommended every 2 years or 40,000 kilometres, while long-life Organic Acid Technology (OAT) antifreeze can extend the replacement interval to 5 years or 250,000 kilometres. Flushing effectively removes scale, rust, and gelatinous deposits from the cooling passages, particularly important for older vehicles or those operated in hard water areas. Such deposits can reduce cooling efficiency, increasing the risk of engine overheating by over 40%. The procedure must strictly follow protocols including engine cooldown, reverse flushing, and professional system evacuation. For instance, the radiator cap should only be opened after engine temperature drops below 50°C, and a pH-neutral specialized cleaner must be circulated for at least 15 minutes. Even for so-called "maintenance-free" models, cooling system purity should be inspected every 8 years with servicing performed as needed. Proper coolant maintenance can extend engine life by 30% while preserving fuel efficiency. Always use OEM-approved products meeting JIS K2234 or ASTM D3306 standards, as substandard coolant may corrode the water pump and radiator, potentially resulting in repair costs exceeding RM500.
