How to Replace a Chevrolet Silverado Fuel Pumpby Chris Moore
A bad fuel pump in your Chevy Silverado will lead to poor gas mileage, and eventually cause the truck to not start at all, so the pump needs to be replaced immediately. Like many pick-up trucks, the Silverado's fuel pump is within a module stored inside the fuel tank. The pump cannot be serviced outside the module, so you must replace the entire module and remove the tank to get to it.
Relieve the pressure within the fuel system. Open the gas cap on the side, remove the fuel pump relay from within the fuse box, then start the engine and let it run until it stalls. Disconnect the negative battery cable afterwards, then siphon the fuel out of the tank into a gas container.
Raise the rear end of the Silverado on jack stands and block the front wheels. Use an allen wrench to remove the screws mounting the flange for the door to the gas cap. Disconnect and remove the shield over the tank and the filler pipe's ground strap.
Remove the EVAP canister by disconnecting the hoses from the canister and removing the bracket mounting bolt. Disconnect the fuel supply and return lines; press the retaining tabs for plastic quick-connect fittings, while using a fuel line separator tool for metal collar fittings.
Support the tank by raising a transmission jack underneath it, then unbolt and remove the straps and lower the tank. Unplug the electrical connectors to the fuel pump module, disconnect the filler hose from the tank by loosening its clamps and remove the tank.
Disconnect the EVAP and fuel lines from the pump module on top of the tank. Release the locking tab on the retaining ring with a pointed instrument, while rotating the ring counter-clockwise with locking pliers. Lift the module out of the tank.
Clean the surfaces of the tank, and make sure the new pump module has a fresh seal. Align the fuel line fittings with the lines as you install the module in the tank, pressing the module down until it is seated. Install the retaining ring, making sure it is fully seated, and the locking tab is within the ring's slot.
Install the fuel tank back on the truck in reverse order of removal.
Re-pressurize the fuel system. With the fuel pump relay connected and the gas cap closed, turn the ignition on for 2 seconds, then shut it off for at least 5 seconds. Repeat this procedure five to ten times.