See also:

Tachometer
The tachometer displays the engine speed in revolutions per minute (rpm). For a description of how Grade Braking affects vehicle speed while the Tow/Haul Mode is activated, see Tow/Haul Mode on page 9 ...

Engine Air Cleaner/Filter
If the vehicle has a diesel engine, see “Pickup Models” under “Engine Air Cleaner/Filter” in the Duramax® Diesel Supplement for the correct inspection and replacement procedures. See Engine ...

Cruise Control
With cruise control, a speed of about 40 km/h (25 mph) or more can be maintained without keeping your foot on the accelerator. Cruise control does not work at speeds below about 40 km/h (25 mph). Whe ...