The Caltex 'Extended Life Coolant' concentrate and premix is an excellent product. The premix uses
de-mineralised water too It has wide approval from European car makers (Mercedes, VW, Audi etc ) and most truck
makers with many alloy components.
It is silicate free, contains a nitrite booster and is based on carboxylate technology which is ideal for iron and aluminium
alloys and is also Phosphate free!
I have nothing other than a commercial relationship with
oil companies - so no axe to grind (My cars and trucks run Shell and Mobil
For warranty reasons only I use Detroit Coolant Premix
in my trucks - I think it is actually made by Mobil to stringent Detroit
specs - Doug H '89 S4