Discoloration on Brake Rotor. What is it?

[jtwoods4]

Hey Guys,

Today I removed my rearend on my 69 GTO. I noticed some discoloration on the rear driver side Wilwood disc brake rotor. Anyone know what this is? Her is a video showing what I am talking about.

http://www.youtube.com/watch?v=YMZahmpQ_5o

[Northern Goat]

Probably e brake rubbing. Had the same issue with my Wilwood rears. Just backed off the adjuster. It must have been minimal rubbing as wheels were never hot to the touch

[jtwoods4]

Thanks.