"Engines produce a lot of heat. Of the heat produced by burning fuel and air, less than 40% is used to overcome friction and push the vehicle. About 30% of the heat goes through and out the exhaust, leaving 30% to be handled by the cooling system."

Skipping down the page and summarizing the article, may I refresh your memory about more useful information. Water is the best coolant but absorbs heat however it has serious disadvantages. It evaporates, creates rust and corrosion in the engine leaving mineral deposits in the radiator, boils easily and freezes too easily.

Antifreeze is a glycol chemical available in ethylene of propylene formulation. Mixing antifreeze with water can drop the freezing point of the mixture to as low as -92 degree F.It can also raise the boiling point to as high as 330 degrees F.

The coolant filter's purpose is to remove common problems like abrasive contaminants that result from oxidation causing rust, scale from minerals, cavitation, foaming and excess acidity.

You may argue, why not just change the antifreeze? I agree but if the vehicle is a large pick-up or semi truck, then the cost of such a choice could be more than necessary. Testing the fluid may show that during use, the filter has removed these contaminants therefore keeping the coolant serviceable.

If your car is the basic commuter's version, think about having this essential aspect checked next time it's in for service. You'll be glad you saw this bit of information when the first blizzard blows through or if you are lucky enough to drive south.