I have an 07 Dakota v-6 4x4. There is an intermittent vibration above 55 and it gets much worse when applying the brakes, the Steering wheel shakes badly. This vibration is intermittent and comes and goes at will. The dealer has turned all rotors and drums and balanced the tires but it is still there. I can not get it to do it when I take it in for service!!!!!??? Thanks, Ed