Well, here we are, almost two years later, and more information has come to light. Turns out that both the Honda "green" and the Toyota "red" really were long life formulae all along, but until the last couple of years neither company was quite brave enough to recommend going over 35,000 miles (probably wanted to survey field results from their respective dealer networks - better safe than sorry). Both companies now recommend 60,000 mile changeouts - still conservative compared to GM's recommendation for its DEX-COOL syrup. I went almost an additional year with my Sonata - 23 months. By last September I noticed that both "yellow" jug Prestone and a new SuperTech product were claiming "universal" extended life properties (extended life only if the system was thoroughly flushed with and diluted with distilled water). Since $4.68/gallon for the suspected Prestone sourced SuperTech* is a tad cheaper than $10.99/gallon for Havoline DEX-COOL, and I'm a cheapskate driving a cheap car, the decision was a no-brainer on September 3, 2004. (To CJH who thoughtfully informed me that I "would have to have rocks in [my] head to switch to Dex Cool", I would only offer that I ran the Havoline DEX-COOL "evil brew" in my Honda Accord for over three years with no problems whatsoever.) In any event the SuperTech extended life (blue-green) which according to the ingredients listed on the back of the jug is identical to the Prestone extended life (yellow-green) and Prestone's silver jug (orange) fully compatible and GM-licensed DEX-COOL clone, only differing in marker dye color and the holy-grail GM licensing fee. (Prestone's licensed DEX-COOL is slightly different chemically from Havoline/Mr Goodwrench DEX-COOL - indicating to me that "DEX-COOL" is a performance specification, not a hard and fast chemical recipe.) It's (very) nearly 9 months and the ST dilute coolant in the radiator is green crystal clear, the viewable core passages are all bright-shiny aluminum metal (the same appearance that orange DEX-COOL presented in my Accord before I totaled it) and the car is running as cool as the proverbial cucumber (including an 85 mph canonball run from San Bernardino to Las Vegas and back two weeks ago in 100+ degree F. Mojave Desert heat with the A/C running in full freezeyerassoff mode. Curiously, the factory-fill coolant drained with slight turbidity - unsure whether the juice was approaching exhaustion, or perhaps an additive of some sort was installed at the factory or by the dealer . . . In any event, I feel better about getting the just slightly murky stuff out. Finally, in passing, cangreylegend correctly pointed out that the Japanese coolants use an OAT formula that is slow (several thousand miles) to fully protect the aluminum internals. What he may not have been aware of is that the Japanese juices also contain a stiff dose of dissolved phosphates for that very reason - they adhere quickly to and protect bare aluminum, but are eventually displaced by the organic acid barrier. Should the organic acid barrier be spot-compromised by a wondering stray particulate, the phosphate will supply immediate "healing" until the organic acid barrier can re-establish itself. The Japanese feel the protective qualities of phophates outweigh their potential for coming out of solution and causing havoc with water pump seals. The bearings are actually sealed and internally lubed for life - the "lube" qualities of antifreeze pertain to the junction of the spinning shaft and the ceramic pump seal.
*Much of the back of the jug blather of the SuperTech is identical - word for word - to that of the Prestone products. They all share the same alpha-numeric production and date coding configuration and listed ingredients. As Yogi Bera said - "It's too much of a coincidence to be a coincidence."
