2007 GMC Acadia Owner's Manual - Page 216

Speedometer and Odometer The speedometer lets you see your speed in both miles per hour (mph) and kilometers per hour (km/h). The odometer shows how far your vehicle has been driven, in either miles or kilometers. Your vehicle has a tamper-resistant odometer. If your vehicle needs a new odometer installed, the new one will be set to the mileage total of the old odometer. If this is not possible, it will be set at zero and a label must be put on the driver's door to show the old mileage reading when the new odometer was installed. If the mileage is unknown, the label should then indicate "previous mileage unknown". Safety Belt Reminder Light When the key is turned to ON or START, a chime will come on for several seconds to remind people to fasten their safety belts, unless the driver's safety belt is already buckled. The safety belt light will also come on and stay on for several seconds, then it will flash for several more. This chime and light is repeated if the driver remains unbuckled and the vehicle is in motion. If the driver's belt is already buckled, neither the chime nor the light will come on. Tachometer The tachometer displays the engine speed in revolutions per minute (rpm). 216