Scratches or some kind of road film?

[Planenut]

I am upgrading to taller segment protectors and trying to clean this area that is above the shorter ones.

It doesn’t seem to clean so I’m beginning to think they are small scratches and maybe some corrosion starting. What do you think? Have you seen this before?

Thanks

[RivetED]

That's fillaform (corrosion). If you look closely at many of them you will most likely see where tiny rocks/debris has hit the coating making a pin-hole that gets it started.

[Planenut]

That’s what I had guessed..

There is not much to do about it I imagine until you are far enough along to polish the entire trailer?

[RivetED]

CorrosionX or Boeshield T-9 are the best products I know of that is supposed to stop/minimize filiform.

I haven't looked into filiform for a while, try searching these forums and there will be a lot of threads about it.