I have a 2007 PT Cruiser with about 89,000 miles on it. It has three new tires, one older that doesn't have much wear on it but still needs to be replaced. When I decelerate from 70mph down, the car shakes and steering wheel/front of the car shakes-it was really bad last night when having to turn the steering wheel slightly. It sounds like it's in the undercarriage somewhere-not engine related. It doesn't do this necessarily when accelerating, or when going slow-just slowing down from higher speeds. Does anyone know what this could be and possible the cost/time to fix? Thank you!