THIS is how to undercoat a frame! I just cut some welded-on aftermarket exhaust hangers, so I can't spray the inside of the rail below that crossmember until I can wash the grindings out.
It took a few days in the sun for this stuff to dry, but it has held up well through some snow/ice/salt and a few years of daily off-roading on my property. Since using up this stuff, I buy Rustoleum from WalMart.
Rustoleum SiteCan Label .
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