The BMW M4 requires 5 liters of coolant. The full name of coolant should be antifreeze coolant, meaning it has antifreeze properties. Coolant prevents the liquid from freezing in cold winter conditions, which could otherwise crack the radiator or damage the engine block or cylinder head. Many people think coolant is only used in winter, but in fact, it should be used year-round. Precautions for using coolant: 1. Try to use the same brand of coolant. Different brands use different metal corrosion inhibitors, so mixing brands is not recommended. 2. Most coolants have a shelf life of two years (some products may last longer). When adding, ensure the product is within its validity period. When replacing, drain the old coolant, clean the cooling system thoroughly, and then add new coolant. 3. Avoid diluting with water. Traditional inorganic coolants should not be diluted with water, as this can cause sediment formation, severely affecting the coolant's performance. Organic coolants can be diluted with water, but excessive dilution should be avoided. 4. For vehicles using coolant, never top up directly with tap water. Instead, use distilled or deionized water. If unavailable, boiled and cooled water is better than tap water. If coolant loss is due to leakage, replenish with the same brand of coolant. Coolant should be used year-round; using tap water in summer is unscientific and counterproductive. 5. Some coolants may develop small flocculent precipitates after a year of storage, usually caused by additive separation. This does not mean the coolant should be discarded. However, if large particle sedimentation occurs, it indicates the coolant has deteriorated and should no longer be used.
