I had this problem right after I changed tires once. I apparently tweaked the rotor during the tire change. I ran a dial indicator on it and bent it back to staight and now all is well, just a thought

 

I originally thought it might be the rotor at first,if this is the case would this covered under warrranty?

 

I was at the dealer today and I do indeed need a new rotor,it is warped really bad and is covered under warranty, should be in next tuesday,they told me that they've replaced 4 or 5 already this year,maybe a bad batch.

Mike.