Principles of Operation - Fuel Tank Selector Valve, Diesel Engines

The fuel tank selector valve and fuel tank selector switch allows the use of 2 fuel tanks. The dual fuel tank option is available only on diesel equipped vehicles. When the fuel tank selector switch is in the front position, the fuel tank selector valve will allow fuel to flow from the auxiliary fuel tank and when the fuel tank selector switch is in the rear position the fuel tank selector valve will allow fuel to flow from the aft-of-axle tank. The fuel gauge will read the correct amount of fuel in each tank depending on which tank is selected with the fuel tank selector switch.