I'm in So Cal and use NO antifreeze in my aluminum radiator. I use a water pump lubricant only. Works great. Also, make sure your engine is ground properly or you might have an electrolysis problem.

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1963 Falcon Conv 5.0L, EFI, AOD, Mini Tub, MII, Big Discs
1963 Ranchero 5.8L, 5spd, Miny Tub, MII, 1 pc windows, Mini Tub, Big Discs
1968 Mustang under construction