2007 ford expedition overdrive button: overdrive

https://www.f150forum.com/f74/floor-shifter-knob-change-how-2007-screw-pics-239428/

Here is a video

2007 Expedition Ford

https://www.amazon.com/2007-Ford-Expedition-Parts-and-Accessories/e/B004CGCNBW

You told us the issue or problem

Now what is the question ?

The chain tensioners got loose ,maybe &
I would guess that the chain guides broke,
because they are plastic & that is what they do
So off came the chain

Now you have a lot of work to do or
someone does

The shift knob is part of the shifter handle. The overdrive shift button assembly and button cover are replacable seperately. To remove the button, simply pry off the cover, pull out the button and replace. reverse the order to assemble.

To remove the shift handle, remove the ignition cylinder by turning to the run position and pushing a small pin, drill bit or allen wrench into the hole on the bottom of the trim cover hole to release the ignition cylinder. Pull the cylinder out. Next remove the screws from the bottom column trim cover and remove the upper trim. Next, remove the pin from the shifter and disconnect the electrical connector. Replace the shifter and reassemble. Good luck, please ask for more information if you can't leave four thumbs up. Have a great day!

you can not remove just the cover it is a sealed unit

This blinking light indicates a problem. You will have to have it scanned for trouble codes to find out
what it is.

overdrive switch on shifter

That part is only serviced with the sift arm. Source: 20 years at a Ford Dealer as a Technician.

OK, here is an update - The torque booster pump broke, so I had transmission rebuilt at Benchmark. So far a year and 20K miles later we have no problems.