96 Windstar brake problems

I have a 96 windstar that I am having problems with my brakes. This is a problem with the braking without the ABS being fuctional. At hiway speed if I step on the brakes I get a vibration like an out of round rear drum. I have replaced both drums and rotors. I have inspected and packed the rear bearings and cleaned all the rear ABS parts. I have no indication that a front bearing is bad or any front end parts. I do have a cracked sensor retainer on the passengers side ABS sensor in front. This is why I have the ABS fuse pulled. Is it possible that the cv could be bad and allowed the gear to have hit the sensor and broke the retainer? A bad Half shaft? A bad Bearing? Like I said I have no real indication that any of these are bad, other than the vibration while slowing down. Any way of figuring out what might be doing this? Sensor problem a seperate problem or related? Hate to put new sensor in until I fix other problem! Any thoughts would be apreciated! Thanks: denkath