NorthStar Pressure Washer Pump Antifreeze Lubricant, 4 Oz., Protects to 25F, Lubricates Pistons, Seals, Valves Northern Tool The cooling system plays a critical role in ensuring the engine operates smoothly and efficiently. To prevent the engine from overheating and ensure it runs optimally, the coolant must be at the Water pump lubricant additives, any benefit? BobIsTheOilGuy Why is Coolant Leaking After Replacing My Water Pump? Jerry