Protecting Your Engine with Coolant

Kenworth T680

Coolant does much more than cool your engine. It protects your engine and other components from liner pitting, scale, corrosion and freeze damage in cold weather. This happens by combining these components in proportions appropriate for the application:

  • Glycol
  • Distilled Water
  • Inhibitors

Glycol provides freeze protection, while distilled water improves boil-over protection and helps dissolve inhibitors. Inhibitors provide protection against erosion, corrosion and cavitation or pitting of your cooling system components.


Without the right inhibitors in the correct proportion, an engine can quickly be damaged, resulting in the following:

  • Cavitation: Air bubbles create tiny pits that grow larger over time in liners and water pumps.
  • Water pump failure: Improper coolant chemistry or low coolant levels can take out a water pump.
  • Inhibitor dropout: Inhibitor literally "drops out" of the coolant, clogging radiator passages and low-flow areas including oil coolers and heater cores.
  • Corrosion: Most often seen in radiators, engine blocks and liners, wherever components are exposed to air.

These issues can eventually put a truck out of service when it's least expected so it’s critical to ensure your coolant’s chemistry includes the best inhibitors.

Contact your local MHC dealer to learn more about the best coolant for your engine.

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