Ford Repair: fuel gauge not working, ford f 250, fuel gauge

Question
I have a 1974 ford f-250 highboy and recently the fuel gauge stopped working. Can you tell me how to diagnose the problem?

Answer
Joe, 9 times out of ten, the problem is inside the gas tank.  As far as diagnosing the problem, you might shake on the wire that comes from the fuel tank and see if the gauge moves any.  That wire is for the sending unit.  Odds are that the sending has went out.  Dropping the tank is fairly simple.  Change the sending unit and also, be sure to put a new float on the unit.  This is also a great time to spray some undercoating if you are up North where they use salt on the roads a lot.  Good luck and if you have any more problems or questions, feel free to ask.    Jason