I believe the engine mounts are failing on my taurus. If I accelerate hard from a complete stop I hear a clunk under the floor board and I feel the vibration in the console shifter. When I engage the car into gear and roll backward I get the clunk as well. I have gotten it going forward right after I engage the tranny as well. So, I think it is the motor rocking. How are is it to change mounts on these cars?