I just bought and put on my roto tech rotors for the front of my car. But now when I hit the brakes it starts to pulsesate and the steering wheel shakes. But sometimes it seems to get better but then gets worse again. I don't have the exspense pads but not the cheap pads either. I know that there was a guy who had them on his car but can't find his thread. Please help if you know how. Also every thing is tight and it didn't do it before.