A couple yrs ago I had a welding deck built for my truck,after a 2 hr wash underneath it looks like the gravel roads won!!

So my question is,what should I redo it with that will standup?

I've seen guys completely coat their decks in box liner spray on but I remember 1 guy saying something about an "iron oxide"?He said it will never come off.

The iron oxide he is talking about is probably rust.

Annual oil spray !!

Spray or roll on Bedliner

Not sure what a "welding deck" is? Is it something you weld on?

Simple can work... red rustoleum primer, satin black and undercoat near the wheels.

Powder coat won't hold up to rocks & debris kicked up by tires.

Go to your local LineX or RhinoLiner store take your wheels off & let them blast away with their product.

When I do a frame off car that the customer is actually going to drive the car. I carry them the car on the rotisserie etched primed out & taped my way with their tape I have them to do the wheelwells,underside & inside the 1/4 panels
The stuff lasts longer than any DIY bedliner does.

My buddy did his custom rear fenders for his KW with it & he said it keeps the outies from being so bad