The spark plugs on a 2000 Ford Expedition 4.6L V8 are located on
top of the engine, between the valve covers. They're fairly accessible, but you'll need a socket, wrench, and possibly a spark plug socket extension to reach them all easily. You might also need a spark plug gap tool to check and adjust the gap if necessary.
Remember to consult a repair manual specific to your year and model for precise diagrams and torque specifications. Improper torque can damage the engine.
