The display is able to be changed. It can be a "dealer only" adjustment. Is your tractor a Premium 7330? If so then it can be adjusted with Command Center display. If it is not a Premium model and does not have Command Center, then it is a dealer only adjustment. A computer will need to be plugged in to access the setting. The BCU controller needs to be accessed and change setting on address 24. There is a 2 digit number at address 24. A "10" will be for audible turn signal with MPH reading, a "11" is audible turn signal and KPH readings. "00" is for silent turn signal and MPH, "01" is for silent turn signal and KPH.