I hear you and feel your pain. Hyundai seems purposely vague, and the dealers aren't much help, either - usually installing the cheapest traditional Prestone clones they can find at traditional dealer-inflated prices. (One Hyundai dealer in Ontario, California actually had several cases of Pep Boys antifreeze/coolant stacked within view of customers in the parts department when I went in to pick up some touch-up paint!) I have a 2003 Sonata V6 I bought new in December, 2002. Last September I decided to change the coolant out early - and I'm glad I did. The old juice was slightly cloudy, though neither outright sedimentation or discoloration. Contrast this with my previous car, a 1996 Accord, which after four years, the original coolant drained clear as spring water, tinted green. I'm betting Hyundai uses the traditional green-snot-of-death antifreeze. (heavy on nitrites, amines, and gell-prone silicates) I replaced it with WalMart's recently introduced extended-life antifreeze (blue jug - a clone of the recently introduced Prestone extended-life - yellow jug, both green, neither contains silicates, and I'd bet dollars to donuts that Prestone makes WalMart's juice since the product date codes on the backs of the jugs use the same alpha-numeric combinations. Some of the wording on the features is suspiciously similar, too.) It's over six months and everything's bright, clear green in both the radiator and the overlfow tank. (I've been keeping VERY close tabs.) The engine continues operating well below the midline of the temperature gauge, too, nor am I losing any noticeable fluid level. For what it's worth, these two green extended-life antifreezes, WalMart's SuperTech, and the new Prestone, are really very closely related, if not identical chemically with Prestone's own "Fully GM Approved DEX-COOL" juice in the gray-silver jugs. (All three read identically on the backs of their respective jugs regarding ingredients.) But the cheaper stuff is dyed green instead of orange, and there's no extra charge for Prestone paying GM's "DEX-COOL" trademark licensing fee. Think of these two cheapies as generic "dex-cools". On the other hand, if you're a dyed-in-the-wool DEX-COOL hater, I would imagine Zerex G-05 would be good, too, as well as either the pricey Honda green or Toyota red antifreeze/coolant concentrates. The latter two contain no silicates, but a relatively high dose of phosphates as added corrosion protection. G-05 has no phosphates, but does contain reduced levels of silicates. DEX-COOL types are both silicate and phosphate free. All contain organic acid technology as their long term corrosion inhibitor chemistry. Whatever you decide on, flushing and diluting with distilled water is highly recommended - Doubly so if your Hyundai has the all-aluminum V-6.
[ March 30, 2005, 05:40 PM: Message edited by: Ray H ]
