Heavy Duty engines have different requirements than their gasoline cousins.  Fuel and oil requirements must meet different standards.  Of particular interest to us is coolant and cooling systems.  Diesel engines have much more compression than automobiles and hence generate more heat.  Additionally, diesels have a unique characteristic .  Usually, a diesel is a wet sleeve type engine.  This means that there is a metal liner that separates the coolant from the combustion chamber.  When the engine is operating this jacket transfers the heat of combustion to the coolant on the opposite side of the sleeve.  When this explosion of fuel takes place there is significant vibration transferred to the coolant through the liner.  This vibration causes bubbles to form on the coolant side of the liner.  As these bubbles implode, at 60,000 PSI they pit the liner.  If this condition is allowed to continue, eventually the liner will pit through and catastrophic failure will take place.  With holes in the liner, fuel transfers to coolant and coolant into the cylinder.  Of course the engine cannot operate under this condition and hence the name catastrophic failure.  How then do we prevent this occurrence.     Most, if not all diesel engine manufacturers require SCA products to be added to the Fully Formulated coolant.  (See the glossary pages for definitions).           

The cooling system in a Heavy Duty vehicle is even more vital to its operation than that of an automobile.  The Heavy Duty engine has more demand placed on it than the typical automobile.  A Heavy Duty diesel engine also has a very different cooling system than automotive.  The diesel usually has a water jacket that envelops the cylinder.  This jacket of coolant insures the transfer of heat from the combustion chamber to the cooling fluid.  If this jacket is penetrated, catastrophic failure results.  In order to prevent this liner failure, certain chemicals provide a level of protection to insure that the metal is not damaged as a result of the intense vibration caused by the combustion of the fuel in the cylinder.

Many factors such as Cylinder Cavitation, Radiator Failure, Water Pump Cavitation, Inhibitor Drop Out and Scaling, can cause premature engine failure.

Finally, never use Automotive coolant in a Heavy Duty application.  Remember Automotive coolant in not likely to have the SCA chemistry required for Heavy Duty cooling system applications.  However, Heavy Duty coolant may be used in Automotive applications.