They are going to show rust no matter what you put on them. Each leaf rubs the paint off the one above exposing raw steel. No paint will hold up to this, so use what ever you have and expect to touch them up every so often if you don't like rust showing. Grease doesn't work any better, it to wears away and rusty stains show back up. I am using a poly liner between each leaf, so far so good (6 + years). The ride is better, the noise is less. and no rust stains.
Joe
