Krabby I address this every year on my Tacoma since the frame was replaced under the frame campaign. My tacoma takes quite a beating and even though it has some underbody protection, the frame still takes a few licks, I address these "repairs" in the winter after my wheeling season is done. To do this I take the following steps:
-Use a die grinder to zap off the rusty spots making sure to go to the edge of where good paint is meeting metal (Do this with finest/ least abrasive allowable grit. If the rust is new and minimal, a coarse grit is not needed. But gouges in the metal will make getting down to the rust more difficult and a more abrasive pad might be needed)
-Clean surface with denatured alcohol until zero residue visible on cloth (I use white shop rags) and allow to dry
-Prime with Rustoleum Farm and Implement Grey primer (Brush on type, Not rattle can, for a heavy application)
-allow at least 24 hours to dry
-Paint with Rustoleam Farm and Implement Black Paint (Also brush on type for heavy application)
I have had great luck with this procedure and products holding up. The result of the paint being laid on heavy with a brush may not be aesthetically pleasing compared to a rattle can variant, but the durability is superior in my opinion...and its a frame, not a body panel
