Rust Preventative Undercoating...
I am trying to figure out what is the best way to prevent future corrosion and rust from showing up on my 1997 F-350 7.3 PSD. I have just removed the bed, sand-blasted and painted. Looks new under there. Now, what is the best "stuff" to spray under there to protect it all?? Should I get WD-40 in a 5 gal. drum and run it through a garden type pump sprayer, or a 5 gal. drum of hydrolic fluid (H. fluid is low cost) and run it through a compressor/spray gun? Or something else??? I figure I would run this through my local area since we have to deal with cold winters and lots of salt!! I hate salt on the roads!!!