ยง393.82 Speedometer.
Each bus, truck, and truck-tractor must be equipped with a speedometer
indicating vehicle speed in miles per hour and/or kilometers per hour. The
speedometer must be accurate to within plus or minus 8 km/hr (5 mph) at a speed
of 80 km/hr (50 mph).
[70 FR 48054, Aug. 15, 2005]