Since your manual specs "Ethylene-Glycol", regardless of color of the original fill (red probably), it was the same as more commonly available Prestone-type green brews. First off, check your current radiator cap. If there're any signs of gasket deterioration, or corrosion or other deposits, replace it. If your engine's been running a bit hotter than previous summers, replace the thermostat. These things do poop over time and if yours freezes up in the closed position on a hot day, you will walk or you will sustain severe engine damage. Period. New caps and thermostats are too cheap to take a chance when in doubt. If you intend to stay with conventional antifreeze technology, they're still available, but there're even better choices*, too. Current Toyota choices are pink (premix) and red (concentrate) which are considered long life. They're still ethylene glycol, but use organic acid and phosphates as the hybrid corrosion inhibitor package - much longer-lived than previously used high dose silicates. (The conventional antifreezes still available use much lower silicate dosing - just as effective as it turns out but much less prone to precipitate out as a gooey sludge or as damage causing hard particulates. Their chief disadvantage now is a working life limited to about two years.) Another hybrid antifreeze is Zerex G-05 - it uses OAT, too, but substitutes reduced silicate levels for the Japanese preferred phosphate content. Either should give at least 3 years of useful service. (Zerex claims 150,000 miles/5 years.) The final choice is DEX-COOL(tm) or one of its unlicensed "dexclones". These rely on OAT exclusively for corrosion protection. They also work well and protect up to 150,000 miles/5 years as long as the cooling system is air tight. (The presense of air causes weird and nasty results.) I used Texaco's genuine licensed DEX-COOL(tm) in my '96 Accord aluminum I4 for over three years with no problems. I've used WalMart's Prestone-made dexclone for nearly two years in my '03 Sonata aluminum V6 with excellent results to date. You've definitely got choices - and none of them are bad.
*If you decide to convert to one of the long-life products, definitely do a full flush with distilled water repeatedly until nothing but clear, uncolored water drains. Ethylene glycol does not deteriorate in use. Your old antifreeze's corrosion inhibitors are about shot. Follow Buford T. Justice's excellent 35 step guide posted elsewhere in these discussions. The monetary waste of distilled water is minimal - WalMart sells distilled water for ~70 cents/gallon or less. In a Camry, five or six gallons will be more than enough. Buy your antifreez as concentrate, not premix. Once you've completed flushing, the liquid still remaining in your cooling system will be about half the capacity and nearly pure distilled water if the last drain was water-white clear. Just happens that a gallon of concentrate should top your system up leaving you with the desired 50/50 concentration. Be sure to remove the plastic overflow bottle and thoroughly rinse it out, too.
[ July 31, 2006, 04:30 PM: Message edited by: Ray H ]
