Coolant is Critical to your Subaru:
Engine coolant serves three important functions: to avoid overheating of the engine; to avoid freezing of the system and to avoid internal corrosion. Each is critical to engine operation and durability. Let’s take a look at each function individually:
First, the coolant keeps the engine from overheating, which can destroy gaskets and other non-metallic materials; create warping and damage to metallic components and cause improper combustion problems. When used correctly, the latest coolant compounds will protect today’s high-revving engines against higher other temperatures than ever before – and for longer periods before they begin to break down and need to be replaced.
Secondly, the coolant avoids freezing of the cooling system. We used to call coolant “antifreeze,” because in earlier days, it served just that purpose. Now, because coolant does more than just protect against freezing – and the cracked engine blocks and damage to other components it causes – we generally refer to the liquid in the cooling system as “coolant.” Again, modern technology has created coolants that protect against freezing better and longer.
Lastly – and equally important – coolant protects the internal metal components of the cooling system against corrosion and rust. It also protects the rubber, synthetic and fiber-based components against distortion and damage.