How to prevent rust on boltholes in truck bed?

[tbird94]

I’m considering drilling holes in my pickup truck bed to bolt on some equipment. However, I’m concerned about the holes causing rust to form. Is there anything that can be used to prevent rust - e.g. coating the bolts or spraying holes with undercoat?

Thanks!

[Len]

I would coat the holes with either Zero Rust or with epoxy primer and paint. Most undercoating is not a very good choice for this application because it doesn't bond to the metal very well.

[Steve g]

In addition to the ZR, and if practical, I would use a hardware store grade of urathane caulking on both sides of the bolt hole prior to installing whatever bolt is going in. You don't need a lot, the bolt will squeeze most out when you tighten it, but what remains will seal the raw edge of the hole. This used to be done with trim screws used on wheel opening moldings way back when they used to thread them right into the sheet metal.
Steve.