Except, (referring to Tomioka's post too), I have two Fords with JC batts in them and not a bit of corrosion. No felt washers, no special grease, no sacrificial pennies strapped on. I think the difference is that they are not driven long distances, shorter trips so the battery does not overcharge and outgas much. I know it is a terribly small sample size, but should have been the double whammy if the two generalizations were true without a 3rd variable involved, no?Go with East Penn, and you won't have post corrosion! Johnson Controls (now Clarios) are BORN TO LEAK!!