Welcome to GTT Joe!
Is this a new happening or always been this way? All of our larger Deere's run at about 3/4 to the red.
To make sure things are ok, you could blow our the radiator and make sure weeds and other items have not plugged it. Check the coolant to see if its full. Check to see if its time for a coolant change or flush. Next would be to check the thermostat.
Could you give us some more info on your tractor. The year, hours and maintenance? it will help greatly.