Choosing the Correct Coolant for Your Car | Cooling System Service

So often, car owners overlook the coolant in their vehicle’s cooling system. Until it’s too late, that is! As one of the most important fluids in your car, the coolant levels should be monitored. The Everett Cooling System Service experts at carson auto repair can assure that the coolant quality and level in your car’s cooling system meets manufacturer recommendations.

Antifreeze and Coolant

Antifreeze is a component of engine coolant. The primary component of antifreeze is ethylene glycol. Coolant is a mixture of antifreeze and distilled water. The recommended ratio of antifreeze to distilled water is:

50%-60% antifreeze : 40%-50% distilled water

Mixing concentrations of greater than 60% of antifreeze will eliminate the reduced freezing point of the mixture, as indicated by this graph from Popular Mechanics:


The color of an antifreeze is determined by additives for corrosion resistance. Each antifreeze is designed to protect the components of specific engines, per manufacturer’s specifications. Matching colors is not the way to determine which antifreeze to put in your cooling system. It is essential that you understand when you replace/supplement the coolant in your engine be certain to use the same product that is in the system. Check your Owner’s Manual to assure compliance with manufacturer’s recommendations.

Mixing Products

If your car is in danger of overheating, and you only have a product that is not an exact match to the antifreeze in your cooling system, it is better to mix products than to overheat. The experts at Everett Cooling System Service strongly advise that you have a full replacement of the entire volume of coolant as soon as possible! Likewise, if you accidentally mix fluids (e.g. adding windshield washer fluid in the coolant system), it is essential that you have the entire volume of the mixture removed immediately. Be sure that the system is flushed with distilled water (not under pressure), until the water runs clear before replacing with recommended coolant.

Routine Maintenance

Many vehicles do not require that the antifreeze in your system be fully replaced before 30,000 miles. It is essential that you check your Owner’s Manual and follow manufacturer’s recommendation for exact maintenance requirements. Although the cooling system is a closed system, the coolant level does diminish over time from evaporation, overflows, etc. It is good practice to have your coolant level checked every time you have your oil changed. Additionally, if you notice a drastic drop in coolant level, it could indicate a leak. Have Everett Cooling System Service experts at carson auto repair perform a full inspection of the cooling system for leaks. To prevent the effects of leaks, have your cooling system inspected at least once a year.