2001 GTP has started a moderate vibration when braking above 65 mph. The vibration all seems to be felt in the steering wheel and none in the brake pedal. During normal driving without braking, there is no vibration at any speed. Also when braking below 65 mph, there is no vibration. This vibration was there before and after a wheel rotation and balancing. I am leaning towards warped brake rotors, but wanted to get your opinion first before I start into the repair. Am I on the right path or should I look into something else?