C 20 3/4 Ton Pickup 2WD V8-350 5.7L VIN L 4-bbl (1983)
Fuel Tank Switching Valve: Description and Operation
Auxiliary Fuel Selector Valve
NOTE: This information applies only to vehicles equipped with auxiliary fuel tank option.
An auxiliary fuel tank switching valve, controlled by an electrical switch, allows selection of either the primary fuel tank or auxiliary fuel tank.
