Coolant and antifreeze are not exactly the same thing, but the terms are often used interchangeably. Antifreeze is the concentrated chemical liquid that helps prevent freezing and overheating.

A coolant flush is a maintenance procedure that completely removes old coolant, rust particles, scale deposits, and contaminants from the engine cooling system before refilling it with fresh coolant. ···

Bleeding a coolant system means removing trapped air from the engine cooling system after replacing coolant, repairing cooling components, or fixing a coolant leak. Air pockets can prevent coolant fro···

The short answer: Add coolant through the coolant reservoir (overflow tank) or radiator fill neck when the engine is completely cold. Use the correct coolant type specified by the vehicle manufacturer···