1. Preparation:
* Safety First: Disconnect the negative battery cable. Work in a well-ventilated area.
* Gather Tools: You'll need jack stands, a jack, socket set (various sizes), wrenches, screwdrivers (Phillips and flathead), fuel line disconnect tools, pliers, safety glasses, gloves, rags, and potentially a fuel pump removal tool (depending on the access). A fuel pressure gauge is also recommended to ensure the system is depressurized after you're finished.
* Gather Supplies: New fuel pump assembly (ensure it's the correct one for your vehicle), new fuel filter (recommended), new fuel pump gasket (if needed), possibly new hose clamps.
2. Accessing the Fuel Pump:
* Lower the Fuel Tank: This is usually the most challenging part. You'll need to access the fuel pump through a port on the bottom of the fuel tank. This often involves:
* Raising the Truck: Securely lift the rear of the truck using jack stands. Never work under a vehicle supported only by a jack.
* Locate the Fuel Tank Access: This is typically located under the truck bed. You may need to remove some plastic covers or other components to get to it.
* Disconnect Fuel Lines: Carefully disconnect the fuel lines using the appropriate disconnect tools. Be prepared for some fuel spillage; use rags to soak it up and be aware of fire hazards. You'll likely have to depressurize the fuel system before disconnecting.
* Disconnect Electrical Connections: Disconnect the electrical connector to the fuel pump.
* Lower the Fuel Tank: Some models require partially lowering the tank, while others might have a dedicated access panel. Refer to your repair manual for the proper procedure. This often involves removing bolts and using straps to support the tank as you lower it.
3. Fuel Pump Replacement:
* Remove the Old Fuel Pump: Once you have access, you'll need to remove the old fuel pump assembly. This usually involves removing retaining bolts or a retaining ring. A fuel pump removal tool can help.
* Install the New Fuel Pump: Install the new fuel pump assembly, ensuring the gasket (if applicable) is properly seated.
* Reassembly: Reverse the steps from section 2. Make sure to reconnect all electrical connections and fuel lines securely. Tighten all bolts and clamps to the manufacturer's specifications.
4. Testing and Finishing:
* Lower the Tank (if applicable): Carefully raise and secure the fuel tank back to its original position.
* Reconnect Battery Cable: Reconnect the negative battery cable.
* Check for Leaks: Check for leaks around the fuel lines and connections.
* Start the Vehicle: Start the engine and check for any issues. If everything is working correctly, check for fuel leaks, listen for unusual pump noises, and verify the engine's performance is normal.
* Fuel Pressure Test (Optional but Recommended): Use a fuel pressure gauge to confirm the fuel pump is operating at the correct pressure.
Important Considerations:
* Repair Manual: A repair manual specific to your 2000 GMC Sierra is invaluable. It will provide detailed instructions, diagrams, torque specifications, and safety precautions.
* Professional Assistance: If you are not comfortable performing this repair yourself, take your vehicle to a qualified mechanic. This is not a beginner-level repair.
* Fuel Safety: Fuel is highly flammable. Always work in a well-ventilated area and take precautions to avoid sparks or open flames.
This is a general overview. The exact procedure may vary depending on your specific GMC Sierra model. Consult a repair manual for detailed, model-specific instructions before attempting this repair. Improperly installing the fuel pump can lead to serious damage to your vehicle or even injury.
