Without enough antifreeze/coolant
  your engine can be destroyed quickly.

Radiator fluid acts as a coolant during warm weather and as an antifreeze in extremely cold weather.

Your car will overheat if the fluid in your radiator freezes because the frozen fluid isn't running through the engine to cool it. It could also crack the engine block from the fluid expanding.

A cooling system in good working condition is critical to car safety. Radiator fluid also keeps the metal in your radiator from corroding.

Check your owners manual for how often to flush and change the radiator fluid.The experts say every 30,000 miles or every 2-3 years it should be changed. This is for the green colored coolant. Red and other colors have a longer life. You can buy test strips at your auto parts store that will tell you if your coolant is still effective in it's cooling and antifreezing ability.

According to the U.S. Department of Transportation, cooling system failure is the leading cause of vehicle breakdowns on the highway.

This statistic above shows poor car maintenance of your vehicles cooling system is a real car safety hazard.

Besides looking every direction on the road, you should glance at your dashboard temperature gauge about every 10-15 seconds to make sure it's not near the red zone. The needle should be just below the halfway mark on the temperature gauge when your cooling system is working correctly.

Checking your radiator fluid:

Every modern vehicle has a Radiator fluid overflow compartment that is translucent so you can see where the coolant level is without removing the cap. On the side of the compartment there is a full line and an add line. the coolant should be between the two lines. If it's below the add level add 50% water/coolant to the full level.

The green line is the full line, the red line is the add line in the picture.

If you don't have antifreeze but you need fluid, add distilled water,not ordinary tap water, so mineral deposits won't build in the radiator and cause corrosion or blockage. However, you should keep the correct ratio of water and coolant to prevent corrosion and for the highest level of overheat or freeze protection.

To check the fluid IN your radiator

you will need to remove the radiator cap. DO NOT remove the radiator cap while the engine is hot. The contents are under pressure and many people have gotten severe burns by removing the radiator cap when it is too hot.

Notice the word "caution" on the cap in the picture.
It goes on to say the contents are under pressure.

IF you have no choice, but to remove the cap when hot, use a towel and remove it slowly to release pressure before you get the cap off.

The fluid in the radiator should be at the top of the radiator.

Make sure you keep 50% water/coolant mixture in the radiator. Some people put more antifreeze in during the winter, but never put more than 70% coolant. It will reduce it's ability to carry heat away from the engine and prevent corrosion.

* Keeping your radiator fluid in top shape is critical to car safety.

So what kind and color of coolant should you use?

It used to be the only color of radiator fluid was green. Now antifreeze comes in red, orange, blue as well . If you have an older vehicle with a copper radiator it is best to stick with the traditional green color fluid. It gives the best corrosion protection for copper core radiators.

Aluminum core radiators use the other color stuff which also has longer life of 100,000 miles or five years compared to 30,000 miles or two to three years for the green.  It is important not to mix the long life coolant with the traditional 2-3 year coolant. The reason is,  it will destroy the long-life anti-corrosion properties making it last only as long as the shorter life coolant. There have also been reports of radiators being destroyed by mixing two different types of antifreeze. In spite of this, some antifreeze makers have products they say can be used with any other type of radiator fluid.

It is best to read your owners manual and ask your dealer what the best reccomendation is for your vehicle. it is generally agreed upon that if you are going to change from the green, 2 year antifreeze to the red/orange 5 year stuff, your radiator should be flushed, not just drained, so the long life properties won't be contaminated.

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