I drive my 46 daily and just spray the undercarriage and inner fenders with a hose about 4 times a week. Another good thing to do is spray Crown rust protection in all the little crevases and hood and door hinges once a month or so. It also helps that when restoring my truck I sprayed the undercarriage, engine bay, inside the doors, running boards and inner fenders with Rhino truck bedliner. I also give my truck a quick wash as the crap on the roads dictate. If you keep up on it it only takes about 5 min to give it a bath. My neighbours must think I am nuts though, because i am out there in the dark washing it all the time. That is because I give it a wash when I get home from work