1984 Ford F 250 "test f250 rear axle" Questions

...f250 was shifting hard to all gears and the overdrive light would not go off the speedometer did not work. I replaced the speed sensor on the top centet of the rear axle. That made the truck only ...

...F250 Super Duty pickup, speedometer and tach quit working, then new batteries drained down. What should I look for to fix it? You should look for a qualified repair shop , unless you know how to test ...