2010 GMC Acadia Owner's Manual - Page 287

Driving and Operating Traction control can be turned on by pressing and releasing the traction control disable button if not automatically shut off for any other reason. The StabiliTrak light will flash on the instrument panel cluster when the system is both on and activated. The system may be heard or felt while it is working; this is normal. When the traction control system is turned off, the StabiliTrak light and the appropriate traction control off message will be displayed on the DIC to warn the driver. The vehicle will still have brake-traction control when traction control is off, but will not be able to use the engine speed management system. See "Traction Control Operation" next for more information. When the traction control system has been turned off, system noises may be heard and felt as a result of the brake-traction control working. It is recommended to leave the system on for normal driving conditions, but it may be necessary to turn the system off if the vehicle 9-31 is stuck in sand, mud, ice or snow, and you want to "rock" the vehicle to attempt to free it. It may also be necessary to turn off the system when driving in extreme off-road conditions where high wheel spin is required. See If the Vehicle is Stuck on page 9‑11. Traction Control Operation The traction control system is part of the StabiliTrak system. Traction control limits wheel spin by reducing engine power to the wheels (engine speed management) and by applying brakes to each individual wheel (brake-traction control) as necessary. The traction control system is enabled automatically when the vehicle is started. It will activate and the StabiliTrak light will flash if it senses that any of the wheels are spinning or beginning to lose traction while driving. The traction control disable button is located on the instrument panel below the climate controls. The traction control part of StabiliTrak can be turned off by pressing and releasing the traction control disable button.