My oem brakes on my 2007 GT lasted until 90 000km and I then installed aftermarket pads and rotors which were noisy so I decided to replace all 4 corners with OEM pads and rotors. That was in October 2014, now my car has a really bad vibration when braking from 90-100km/h. I think they should of lasted longer than that without warping? I am thinking maybe the local guy who installed the winter tires with his air impact warped the rotors last fall? I know at my last oil change at the mazda dealer, they told me that my right rear parking brake cable and caliper are starting to seize, maybe that could be it? If the vibration is coming from the brake pedal, how can I tell if it's the front or rear brakes that's causing it or if it's all four of them?