I have a 03 Caravan, when i push the brakes there is a shutter that i can not figure out it feels like its in the rear!. We have had it to 7 different people and no one can yet figure it out, I have replaced the spring hardware kit at first, then drums, then shoes upon also finding one wheel cylinder and adjuster bad, which was changed. So thats the entire rear end of parts minus one wheel cylinder and adjuster. It has bad leaf spring bushing that i have been told can not cause this issue. I have replaced the front brakes and rotors as well and it has had front struts and rear shocks on it maybe 6 months ago. Im literally running out of ideas, it only does it when you hit the brakes i have changed 2 tires because i have thought that be the issue as well and was not. It has got to the point that you can feel in the brake pedal as well and one point of time it felt like it trying to push the pedal like a drum was egg shaped(that was before we changed it) and now once again it feels like its back in the pedal and the shuttering is getting crazy that i cant figure it out please help!