I was also curious about the option of replacing the G12 coolant with something a little more affordable; so, I visited the Prestone website and performed a little research. Prestone indicates that many European car makers recommend phosphate and silicate free coolant, such as G12, due to the mineral content of European water, which has been known to result in heavy corrosion when mixed with this type of coolant. Prestone states that this has not been an issue in the states because our water supplies do not contain this particual combination of minerals; and, as such, recommends their universal coolant (which looks oddly like standard ethylene glycol - AKA the green stuff). My thought is that a proper flush of the cooling system, followed by a switch to standard ethylene glycol coolant might yield acceptable results. Honestly, the engine components (i.e. heads, blocks, hoses, seals, etc) are generally of common material and construction whether foreign or domestic, and the U.S. automakers, like Ford and Chrysler have been using this stuff for years without problems. This being said, I'm still not sure that I'm ready to put my money where my mouth is without further research. I guess we'll find out next month when I replace my leaky radiator and perform the TB/water pump replacement.