They'll oxidize, yeah. It's mostly cosmetic but makes prep a bit of a pain if you need to weld on them.. I'd give them some type of coating to protect them if you're worried about it.
I didn't know you could do clear powdercoat........... but if I powdercoat them I guess I would just prefer crinkle black.... or just spray them myself with bedliner...... this shouldn't be such a hard decision lol
My flat bed and most I have built for fire trucks for 14 years look fine. Most start as polished atp. My personal bed is plain. Regular washing and no strong chemicals. It will natural dull out and stay fairly constant afterward. Aluminum will oxidize to a point and quit. Unlike most normal steels. This then seals the surface. Where it goes bad is with a coating or other substrate that traps water and or chemicals and keeps it soaked. This increased the oxidation and doesn't allow a molecular level film to build halting the process. Another huge enemy of aluminum is galvanic corrosion through dissimilar metals. I highly recommend Stainless hardware, and or nylon washers between coated surfaces. Absolutely stay away from any zinc coated hardware. The gold like used on grade 8 in high moisture areas seem the worse. Except for the tanks I have repaired with hard water or fertilizers in them..... those usually contain electrolysis rods in them and fail in short order.
oh and shawns bumpers are an aircraft grade which inherently fights this process among other qualities it was engineered for..........other than the fact that when you weld it the heat effected zone is almost completely annealed unless retreated.
Go to aluminum on the rears and running boards/sliders and I think it would look pretty sharp. Right now, it looks unbalanced. Potentially, you could plasti-dip them peel it off later if you decide to go raw with the rest.
