A buddy of mine has a side business of spraying ProFleet film. Its done every fall. Pulls out the tail lights, gets in every crack and crevis. Drills small holes along the door jamb to get into all the areas that are not accessible otherwise. So, is it clean underneath? NOPE. The heavy "Slime" that goes on the underside and the thin oil everywhere else collects dust from driving down the gravel roads. Actually helps keep the oil in place and keeps away the rust. But it is a truck that is meant to work, but it does get washed about 6 times of times a year.