MINI Recommends the coolant system drain and refill EVERY 4 YEARS as listed in the 'Additional Service Items' section of Inspection II. This will maximize longevity of the cooling system and its components. The MINI factory recommends this factory anti-freeze/coolant for your MINI. Specially formulated with no Phosphates or Nitrites to ensure compatibility with your MINI Cooper and S. The factory recommends replacement every 4 years but many owners like to change more often. Factory recommends a 50% mix of coolant and water. Coolant comes in one gallon bottles.