Peculiar Black Spots on the Rear End

So I just came from a coast to coast trip and when I got back to California, I noticed some black spots at the back of my truck. I'm not sure where it came from, but washing it won't take the spots away.

I went through snowy spots for several hundred miles, and I presume that's how my truck got those black spots. I will provide pictures later in this thread. But I do need help on taking them off. Thank you and I'll be in this thread all night.

 

clay bar?

 

Hey OP,

I used to live in Cary, great place was sad to leave. I actually get these small black spots on my truck as well they are very small and hard I usually just take my finger nail and gently take it off then wax the residue off I have no idea what the heck it is but I have them all the time. Hope that helps. Welcome to the World

 

@hoenah
I was actually considering that, but I forgot to type that down. But I still can't find my camera. Until then, I'm not sure if clay bar is even strong enough for this.

@brny
Oh man I was originally for CA and moved to NC, but it didn't work out so I came back here again. It was a gorgeous place too. Anyhow, do you know why those spots are on my truck? I'll definitely try waxing it, thank you!

By the way I've also seen some people not liking to put diesel or kerosene on those spots, as they render the paint dull. I was considering that at first, but I'm pretty skeptical about using it now.

 

Use and new microfiber cloths only touch the paint.