Does Overfilling Car Antifreeze Have Any Impact?

[LeHazel]

Overfilling car antifreeze has no negative impact. The excess antifreeze will undergo thermal expansion during vehicle operation and overflow through the pressure relief valve, causing no harm except for leaving some stains. The antifreeze reservoir has both MAX (maximum level) and MIN (minimum level) markings, and the antifreeze should be filled between these two levels. Car antifreeze prevents coolant from freezing during cold winter parking, which could otherwise crack the radiator or damage the engine cylinder block/head. Antifreeze is a special additive-containing coolant primarily used in liquid-cooled engine cooling systems, offering excellent performance in winter freeze protection, summer boil-over prevention, year-round scale inhibition, and corrosion protection.