Best goo and prep for window gaskets?
The rear windows of my bus have some kind of caulk-like goo smeared between the gasket and the bus skin on one side, and between the gasket and the window glass on the other. The stuff seems to have worked as far as stopping leaking, but it's starting to peel off and I need to replace it with something. I've been using Dynatron-500 almost everywhere but I don't think it will work in this case, not least because it's gray and I'd like to use something black (preferably) that I won't have to paint.
What's the best sealant to use here and what's the best prep to do on the rubber gasket (I thought I read something about using baby oil on it)?