DexCool is EG or ethelyne glycol, just like conventional green fluid. The difference is in the additive package. DexCool uses OAT (organic acid tecnology). OAT is becoming more common as a coolant additive. VW / Audi use an OAT coolant, as do others.
I have used DexCool in most of my family cars nearly since it was introduced. I have had no difficulty with it. Most of the positive information I obtained about it was from the Texaco web site which is no longer available. Since Texaco was bought out by Chevron, the detailed information about coolant with OAT technology has been removed.
Ford uses Texaco supplied coolant in three formulations. Conventional green which has been the standby by decades. DexCool which has been factory fill for the 99 and newer Cougar. And newly introduced gold which so far is only used in trucks. Ford does not recommed changing from one type to another. When the gold was intorduced, they did say that studies were underway to see if the gold could be interchanged with green. They have not described the composition of the new gold coolant.
Anyway, Dexcool works great for me.
