Here is what a local brake shop told me about the newer GM pickups.
He says if you don't use the emergency brake the brakes don't adjust, - they get a little loose and the shoe hangs down and rubs on the little drum inside the rotor. The rotor eventually wears out.
I think this is a similar design to the camaro and I'd guess you need to lift the shoe somehow to allow removal of the rotor.
Talk to a local brake shop and see what advice they have.
Here is a link to a Brake trade magazine, they have archives of articles you can search for info.
http://www.brakeandfrontend.com/index.htm
David
