I have a 1999 caravan with around 115,000 miles. I get a vibration braking as speeds over 30 MPH. I have recently replaced the front rotors/pads/calipers and also the rear drum/shoes. The vibration still exists. No vibration in car when driving at any speed, only when I brake over 30. The vibration gets worse when braking at higher speeds. Any thoughts? - Thanks - Mike