Why is it I can only use 1 fuel tank?
Could be the fuel pump inside the tank or your selector switch on your dash board. Wiring-connector that goes to the pump could be unplugged-bad. Turn the key on but don't crank the truck listen to see if you hear a humming noise for about 1 second coming from the fuel pump in the tank. Turn the key on and off.....If no noise you'll have to get dirty and let the tank down to check things out.
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