Need some help here. I've got my abs light showing on dash. I've changed my hub bearings and the sensors were changed. Did not help. Now sometimes the speedometer sticks and the overdrive light blinks on and off. Do i need to change out abs module or what do i need to do to pin point problem. It's a 2000 Ford F250 7.3L 4x4 with 146000 miles.

 

check the speed sensor on the rear diff.
they control your rear abs and your speedometer.
it is right on top of the diff with 2 wires sticking out of it.

 

Yup... Sometimes you can remove the sensor from the rear diff and clean it. Sometimes not... but thats your problem more then likely!