The gas gauge for the front tank on my 1992 F150 is stuck past full

replace front fuel pump because gauge is made into fuel pump and not serviceable. Or poor boy way of getting by would be fill front tank with gas reset mileage drive normal for a day. refill again with gas note gallons used and mileage driven for average miles per gallon. front tank should be around 17 gallons multiply by mile per gallon you figured

the tank selector valve is stuck or not switching when u switched ur tanks

the gas is regulated from the switching valve you control off the dash. Check the valve to hear it switch
have a friend help you do this. it will be located under the truck between the two tanks. You may have a faultly valve or switch rattling inside changing the tanks setting also while driving which will be hard to tell

Trace the wiring from the fuel tank back to the instrument cluster - you have a short grounding out some place. When the sending unit grounds out it pegs up past full.

You may have run out of gas in the front tank, but the gauge may have been reading the rear tank or the front sender is stuck. Is the fuel line switched electrically or manually controlled? How are the gauge connections switched?

You will need to remove the wire for the sending unit on the tank and ground it to the frame with your selector switched to the tank you are working on and the key on. If gauge comes up to full then the sending unit is bad and gauge is good. Repeat process on other tank. The fuel tank switching valve on the frame also switches the wiring signal from either tank for the gauge. If no change with first test you will want to check the valve.

A FORD EQUIPED WITH DUAL TANKS THIS YEAR MODEL HAS CHECK VALVES IN THE FUEL PUMPS .THE FUEL RUNS FROM THE REAR TANK WHEN IT IS POWERED ON TO A TEE AND INTO THE SAME LINE AS THE FRONT PUMP . THE PROBLEM IS AT THE BOTTOM OF THE FRONT FUEL PUMP THERE IS A CHECK VALVE ON THE FOOT AND IT IS NOT WORKING.WHILE THE TRUCK IS RUNNING WITH THE REAR FUEL PUMP ON IT IS PUMPING FUEL INTO THE FRONT TANK . IT WILL RUN OUT OF THE NECK WHEN IT IS FULL.THE FIX IS SIMPLE REPLACE THE FRONT FUEL PUMP. THEY DONT MAKE A CHECK VALVE REPLACEMENT I CHECKED I HAD THE SAME PROBLEM AS YOU.

yea fords with two tanks are known for getting stuck if you dont switch the tank constantly. you have to get to the valve that switches the two tanks, and free it up. it definitley isnt anything but the valve.

The switch that you use to change tanks is probably faulty - the switch supplies power for the sending unit in the tank, and to the transfer switch for the gas lines - use a meter to check it

Have the same problem, its the switch valve, not sure how to fix it yet. But i can tell you thats what it is.