A tread depth measurement system for measuring a depth of a tread provided
to a tire on a vehicle. The system includes an energy source for emitting
a wireless signal to be transmitted to the tire; a sensor for detecting a
return wireless signal emitted from the tire to be transmitted in
response to the wireless signal from the energy source; and a housing
over which the tire is to roll while attached to the vehicle, said
housing separating the sensor from the tire while the tread depth is
being measured. A control unit is operatively coupled to the sensor for
determining the depth of the tread as a function of at least the return
wireless signal detected by the sensor.