Even car enthusiasts are torn over the issue of whether water is better for your vehicle than engine coolant. While both will help keep your engine cool, coolant has a few distinct advantages over water.
It takes a lot more heat to boil coolant than to boil water. This means that coolant can protect your car at much higher temperatures than water and for longer spans of time. This is crucial in summer months, in traffic and on long trips where your car can generate additional heat.
Water inside your car freezes in the winter, so it must be drained out before freezing temperatures set in. When water freezes, it expands, and this expansion can damage the radiator and even crack the engine block. Coolant doesn't freeze inside your vehicle, and therefore doesn't need to be drained in the winter and won't damage your car.
Coolant contains chemicals that work to prevent corrosion. Water doesn't contain corrosion-fighting elements; instead it can contain trace minerals and other additives that can actually cause parts along your car's cooling system to corrode faster.
Water is a more convenient additive than coolant for people in emergency situations, like those in freeway traffic. It's more abundantly available than coolant. This makes it the product many people turn to in emergencies, even if just temporarily.
Coolant is far more expensive than water. A gallon of coolant can cost anywhere from seven to 20 dollars, depending on brand. Most people have free or inexpensive access to water.
