I have a 2001 Ford Windstar w/3.8 V-6. The codes state that #5 cyl has a misfire. I just changed the plugs, put new plug wires on & installed 4 new O2 senors. What else should I be looking for?

Double check the plug wires, if the boot to the plug wire was not installed with spark plug boot lube. It may have pulled away from the plug just enough to make it a bad connection. Go back and push on the plug wire boot to the spark plug and make sure the wires are routed properly and not touching anything other then the separator that hold the wires in place. The other thing would be a dirty injector ir an bad wire to the injector. Start with te plug boots and routing. Good luck friend, I have a Montana and same thing here, take me longer to ensure that all the plug wires are set then to replace the plugs.