I've been using Penrite Classic Car Coolant. It doesn't protect from
freezing, but it does seem to keep things clean and free from corrosion.
It has to be smuggled in from Australia to a guy in New Mexico who's
difficult to get in touch with, and who doesn't take credit cards.
I guess I find that appealing because I bought a case.
In the Honda's, I use Prestone, in case I ever drive someplace cold.
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