On my Diesels I have used everything from PepBoys to Rotella Antifreeze and sometimes I wonder if its Hype. Somethings on Turbobricks and SAABnet you hear members touting the advantages of a certain brand Antifreeze that really lower engine temperature, but if you really think about it, engine temperature heat release is controlled by thermodynamics and not what the intracacies of the cooling fluid are.
The basic component in Antifreeze, Ethylene Glycol, basically keeps the 40 to 60 percent water component from boiling over. The additives inhibit corrosion. Does the actual coolant composition make a difference? Water is the ideal thermodynamic coolant, I mean you can't use Housepaint or Lacquer Thinner, or Salad Dressing (hey could you?) but no miracle fluid is going to absorband transfer heat better than water ( or am I wrong?) I mean thats why water was always the component in steam engines driven by boilers. If there was something better, why did they still keep using water?
Does it also affect the adiabatic properties of the coolant mix? I thought that was controlled by the radiator / fan size and water pump properties and and engine thermodynamics. I mean if you have a teeny tiny radiator, no wonderbrand of antifreeze is going to help. And as long as you have basic anticorrosive additives? I wonder--then why do radiators and heater cores fail nevertheless and always lok the same inside? After all it all copper piping like the stuff in your house..