In 1991, Frank Kelley of Caterpillar wrote: “In warm climates, it is still common for water with an appropriate concentration of supplemental coolant additive (SCA) to be used in heavy duty engine systems. This practice will probably become less acceptable as engine operating temperatures increase and aluminum components find their way into applications in heavy duty diesels in the future.”
That time has now come. Furthermore, as exhaust gas recirculation (EGR) becomes prevalent in 2002 engine designs, additional heat load will be transferred to the cooling system due to cooling the recirculated exhaust gas before its introduction to the air intake. This will further increase the need for the use of antifreeze/coolant due to the need for higher radiator top tank temperatures to handle the greater coolant heat load.
Additionally, use of antifreeze coolants in older engines is very beneficial even though coolant temperatures may not be high.