How complicated is it to change spark plugs - 2000 Ford Expedition

A little not much, disconnect harness from coil pack, then remove the 8mm bolt that holds the coil pack, pull coil pack out and remove spark plug, check coil pack boots not bad idea to replace while in there, do one at a time, make sure to gap new spark plug at .054" both 4.6L and 5.4L are the same gap.Good luck hope this was very helpful.

Hello
It depends.Some autos need to have the front tire removed to get to the plugs.Or the battery is in the way.

Lets say you have a clear view at the plugs.
1. Tools You need a 3/8 ratchet with an 6 inch extension and a 5/8 or 13/16 socket.
2.A blanket or towell to cover up your fender so you dont scratch the paint.
3.A spark plug gap tool.Plug type and gap should be listed on the engine sticker under the hood.
4.Optional-undo positive cable on battery.
5.Start on first plug.DO ONE AT A TIME.pull 1 plug wire off ,and remove spark plug using your ratchet and socket.Set gap on new plug and install into plug hole.
6 Pull one wire and plug at a time so you do not cross wires and mess up firing order.

May sound like alot but its really easy.