2004 GMC Sierra 1500 Pickup Owner's Manual - Page 199

Speedometer and Odometer Your speedometer lets you see your speed in both miles per hour (mph) and kilometers per hour (km/h). Your odometer shows how far your vehicle has been driven, in either miles (used in the United States) or kilometers (used in Canada). Engine Hour Meter Display The odometer can also display the number of hours the engine has run. To display the hour meter, turn the ignition off, press and hold the reset button for at least four seconds. The hour meter will be displayed for up to 30 seconds, or until the ignition is turned on. Trip Odometer The trip odometer can tell you how far your vehicle has been driven since you last set the trip odometer to zero. Press the reset button to toggle between the trip odometer and the regular odometer. Holding the reset button for two seconds while the trip odometer is displayed will reset it. To display the odometer reading with the ignition off, press the reset button. Tachometer Your tachometer displays the engine speed in revolutions per minute (rpm). Notice: If you operate the engine with the tachometer in the shaded warning area, your vehicle could be damaged, and the damages would not be covered by your warranty. Do not operate the engine with the tachometer in the shaded warning area. 3-35