Residue on the back quarter panel

[PDXStangDude]

I've been finding this black residue on the back quarter panel behind the wheelwell. At first I thought it was tar but now I think it is melted rubber from my tires. Actually I'm pretty sure it is, I just didn't expect it to be hazzy black speckles. I figured it would be rubber flakes similiar to what you see on a track just a little smaller.

Anyone seen this with their stock Pirelli's?

 

[Unbrdld07]

Thats why I have the splash guards on mine, that and the fact we had a really wet winter.
Just a footnote since your PDX...Ford is coming to Astoria with the line-up of 2007 models at Pier 1, will be here to showcase the line-up and probably burn some new commercials while they're here. Don't have the date yet but would be fun to see. W@ill post the date when I get it.