Ok so my work truck 04 sd had new brakes and recently the abs light came on... Seems like truck stops fine drives fine everything..... Is there a sensor for it that could be out ect.....
Sounds like the Speed Sensor. That is located on top of the rear end center housing. It has two wires coming off of it. Get a new one from Ford and change it out. No draining of the rear end is necessary, just unscrew and replace it.