Any ideas on a cleaner to remove 2 years of stains. Its from the alum roof panels or the sealer up there. Waxing will do the trick but 24' X 8' (both sides) ,too much for an old guy!
Bill....At the truck washes where I get my truck/trailer cleaned they use an acid that'll take a majority of the stains out. That should work to take the stains on your trailer out. Any truck wash will have it and some of them use automatic brushes that'll scrub the sides of the trailer clean.
If it is the sealer, it is petroleum based. You can use mineral spirits or Castrol SuperClean (NaOH or oven cleaner). Just spray it (superclean), mineral spirits just pour it on, let it sit for a while, 10-15 mins, out of direct sunlight. Use a hand brush or a push broom to mechanically agitate the mix then hose off. Should not take you long. :beer
I had the same problem with my trailer. I went to my local auto store and got a compound by Mcguiers designed for boats and rv's. Its meant fot the fiberglass and it removed everything. They also have a wax meant to go on after that to help protect it and keep it looking good.
