I have a 2004 330i ZHP with 79,000 miles. When I apply the brakes at over 20mph there is a very noticeable vibration - but not in the steering wheel. I have Turner cross-drilled rotors and have checked each one to be true and clean. Thinking that the problem still might be with the rotors, I have changed each one in sequence with other rotors and found that the problem does not go away. I changed the control arm bushings about 2,500 miles ago and they appear to be sound. the ball joints look OK but I have not removed the control arms to check them. I am using Hawk intermediate pads that now have about 3,500 miles on them and they still look good. I changed to my winter tires recently and that has not helped. Anyone have any suggestions?