An Engine's Defense Requires A Good Offense

Actions to take to avoid potential problems

While protection against freezing of a coolant mixture is important, it has little bearing on other protective properties of coolant. If SCA is needed to bring inhibitor protection back up to safe levels, ensure the proper SCA is used as there are different types of SCAs available. For example, NOAT coolant usually requires periodic use of a nitrited SCA at specific intervals to help boost the inhibitor chemistry for adequate protection throughout extended service intervals.

Some fleets may use coolant filters that not only help remove solid debris from the coolant but replenish and help maintain proper inhibitor levels.


Antifreeze comes in a rainbow of colors ranging from green to orange to yellow and every color in between. In general, green has been used for conventional, fully formulated IAT antifreeze; orange used for OAT; and NOAT and HOAT may come in red, pink, yellow (gold), purple or another color. However, never use color as a guide to selecting antifreeze.

It’s very important to know that color alone doesn’t positively identify a specific type of coolant chemistry. Antifreeze is clear and manufacturers add dye to help differentiate their products.

Equipment manufacturers specify different chemistry, not color, for good reason. While one ELC may work well in a specific cooling system, using another type of ELC may cause eventual damage to a cooling system or engine. If in doubt, follow manufacturers’ recommendations.

With all the colors and confusion surrounding ELC, a service technician must be well-informed on servicing cooling systems properly. One possible approach to simplification and reducing confusion may be to use a “universal” or “multi-vehicle” ELC and follow the antifreeze manufacturer’s instructions.

Using the correct type and concentration of antifreeze, along with recommended maintenance practices, fleet managers should be able to avoid many cooling system problems.

Joseph Long is the director of sales for the Power Fleet Division at Penray. The Penray Companies has been the standard of excellence in product quality and service for professionals for more than five decades. Penray sets the pace in cooling system treatments, fuel treatments, and shop chemicals that maximize performance and help extend vehicle life.

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