Hey everyone. Hope you can help! So I told a customer I could remove these stains about half a week ago and went to the job today to do it. Needless to say, I couldn’t… I told them initially that it was the worst oxidation I’ve ever seen. Thinking it was, at the time, oxidation. After today, I’m not so sure. I tried the usual Cleansol BC oxidation remover. I’ve got a soft wash system, no down streaming, so the application was perfect as far as directions are concerned. I even went up to almost 50/50. Way higher than recommended for tough stains. It didn’t do anything… I then tried One Restore thinking it might be hard water stains. One Restore is amazing right and can get it off no problem!! Wrong, It didn’t do anything. I’ve got other chemicals on my truck like Gutter Grenade, rust & battery acid removal. After these 2 chemicals didn’t work though, I didn’t try anything else. Would love some help. I ended up being honest with the customer and let them know I got it wrong. I didn’t ask for any payment. They understood. If you look at the picture closely, you’ll see what look like shoe prints in the stain. It’s almost like someone walked on the siding with concrete on their shoes. Any help identifying this mysterious stain would be very helpful & of course, how to remove it. Thanks in advance everyone!
Got me interested lol 
ill be following along to see whats going on here
While I was there, I would have tried small spot with everything I had, just out of curiosity. Did you try elbow greae or brushing? Aluminum brightener or wire wheel cleaner? Let us know if you ever get figured out.
Yes I tried scrubbing both chemicals in with the hard bristled brush. I used a key to scrape the surface, it seemed to remove some but I wasn’t 100% convinced if it actually did. I didn’t want to agitate the surface more than using a hard bristled brush. I thought steel wool might work from cleaning windows but that’s more than I signed up for & probably a bad idea. It did disappear (almost) completely when wet if that helps. Didn’t think about that when writing the original post. We actually did try polishing the surface with some dash board polish. First time ever doing that. It worked actually but left it shinny & seemed kind of ghetto if I’m being honest. If you have a suggestion on a better polish that would make the shine less obvious, I’d love to hear it.
