You need to go to the owner.ford.com website, register your vehicle with its VIN number. Then go to the SYNC 3 Update area. Ignore the file there that is 4.*** something like that. Ford dispatches the correct file for your vehicle based on the vin number you provided. Download to a 3.0 or 3.1 32GB Metal Case thumb drive;
Centon DataStick Pro USB 3.0 Flash Drive, 32GB, Elite Black, S1-U3E1-32G, $ 12.99, OfficeDepot
The example/suggestion above, the drive is in a aluminum case, SO IT WILL LAST, needs to be kept on your keychain, once you complete the update, its part of your vehicles important records. The 32GB space also allows you to create a folder, VEHICLE DOCUMENTS, and related sub folders for all the paperwork that comes with vehicle ownership. Ford provides the owners manual, in its entirety, in PDF format. Download it to this, keep it on your keychain, you can stick it in any computer and search the owners manual for what you need, as opposed to flipping through page after page. You also have space for any new SYNC updates that come along.
OK DRIVE MUST BE FORMATTED IN exFAT, download the Ford file into a folder you create called SYNC 3 ZIP. Next, using WinZip or some other unzip, zip, program you prefer have the zipped files extracted to the root directory of your thumb drive. The zipped files must be unzipped to the root directory of your thumb drive!!! IE: when you are asked where you want to extract the files to, tell it G:\ (G may not be what your computer system assigns the drive, it could be any drive letter your system decides on. If you did it correctly, when you pull a directory of the thumb drive you should see G:\and a list of the extracted files, the folder SYNC 3 ZIP, and inside that folder should be the zip file. NOT G:\SYNC 3 ZIP\then the extracted files. The vehicle can only install code from the root directory. The USB Port you should be using, in a 2016, is the lower port of the 2 USB ports UNDER THE CENTER ARMREST LID.
In the following link the 2016 Expedition is not listed, try instruction 2 first, no luck, give instruction 1 a shot. I think if I recall correctly for my Sony Premium Sound head unit it was instruction 2.
https://owner.ford.com/support/how-...-and-updates/how-to-install-sync-updates.html
One owner got it done in 30 Minutes, got to be a record, it took me about 2.5 hours cause it crashed in the middle of things my first try, messed up the downloaded files, had to redownload and start over. Important, the crash did not mess up the head unit. If this happens to you turn off the radio, shut off the vehicle, remove the USB drive. Wait 5 Minutes, start the vehicle, turn on the radio, WAIT UNTIL RADIO BOOTS INTO NORMAL OPERATION, then insert the thumb drive into the vehicle USB data port. Then using the set of instructions that worked the first time, (always insert the USB drive after starting the vehicle, turning on the radio), after you figured out which ones, restart the update. If it fails, won't read the drive, etc. Take it inside to your computer, reformat the drive, it must be exFAT, NOT NTFS, OR FAT32, redownload the file Ford provided to the reconfigured thumb drive. Take it back out, try again, using the set of instructions that worked when you first tried. If it fails again, you need to contact SYNC 3 Support for help.
I also made sure my Expedition was connected to the house WIFI for the update. Just in case it wanted to chat with the mother ship.
IMPORTANT: When the update is finished, it poops out a file onto the thumb drive you MUST UPLOAD BACK TO FORD VIA THE DOWNLOAD WEBSITE. I sets up the communications hierarchy between Ford, your vehicle, the internet, tells Ford you did the update, etc.
All finished, all done. Take the thumb drive to your home computer, create a folder SYNC 3 UPDATE COMPLETE, select all the files on the root directory, excluding the SYNC 3 ZIP folder, move them into the update complete folder. Just house cleaning, the next update will be done the same way, and will need to put only its install files on the root of the thumb drive. And you have the previous update in its entirety put away, just in case.
If you have already succeeded with this, congrats! If not, hope this helps. Oh, and if you want your Expeditions AS BUILT file go to this website.
https://www.motorcraftservice.com/AsBuilt