Was inspecting the front rotors while washing the dust off of my wheels on my 04 Supercab and noticed that they already have ridges worn on them. This seems unatural for only 7500 miles. Anyone else seen this. (I've seen it after wearing the pads out but there is still plenty of pad left.)

 

I think it is normal to see small groves in the rotors, anytime you are using semi metallic brake pads it is going to happen.
The harder the brake pads are the more wear on the brake rotors, I have groves in my rotors also with only 3500 miles.
The only way around it would be to use organic brake pads (very soft) they would not wear the rotors but you would have to replace brake pads more often plus they would probably not be as efficient in stopping because of brake fade.

 

There's been others that have had the same problem, and some of these new truck owners have had the rotors turned the 1st time and possibly replaced if the problem reoccurs. Don't rule out the possibility that the rotors could have a quality problem, with the hardness or composition.

 

I just noticed on my 2004 4X4 Supercrew the same thing. I have only 1200 miles of very easy driving. The back rotors are as smooth as glass but the front ones have grooves wore in them. Looked at my wife's 2003 Grand Cherokee and the front ones are grooved a little more than the back but it has 27000 miles on it. Has anyone brought this up to the service shop?