There is a very minor leak on the radiator of my '96 Cherokee. It's so small I haven't lost enough water in 1000 miles to need to fill it. I'm not quite sure where it's leaking from, but I think it's where the plastic tanks go up against the metal of the radiator. I was looking at the radiator sealer products today at Fred Meyer...there's about 15 different brands. Also there's the walnut shell type and then what they call "aluminized". Several different brands - Bar's, Gunk, Alumaseal, etc. What's the best?