Searched the manual....Obviously, well it is now, the truck that I drove did not have the "eco" message icon turned on.
Fuel Saver Display In Cluster
The ECO message is located in the instrument cluster
display, this message can be turned on or off. To make
your selection, touch the Fuel Saver Display soft-key,
until a check-mark appears next to the setting, showing
that setting has been selected. Touch the back arrow soft-key to return to the previous menu.