Your vehicle is equipped with StabiliTrak®, which combines antilock brake, traction and stability control systems and helps the driver maintain directional control of the vehicle in most driving conditions.

When you first start your vehicle and begin to drive away, the system performs several diagnostic checks to insure there are no problems. You may hear or feel the system working. This is normal and does not mean there is a problem with your vehicle. The system should initialize before the vehicle reaches 20 mph (32 km/h). In some cases, it may take approximately two miles of driving before the system initializes.

If the system fails to turn on or activate, the STABILITY SYS DISABLED or SERVICE STABILITY message will be displayed. If the vehicle has gone through heavy acceleration or braking or multiple turns during the first two miles of driving after starting your vehicle, the STABILITY SYS DISABLED message may appear. If this is the case, your vehicle does not need servicing. You will need to turn the vehicle off and then restart it to initialize StabiliTrak®. If either message appears on the Driver Information Center (DIC), and your vehicle hasn't gone through hard acceleration, braking or multiple turns in the first two miles of driving, your vehicle should be taken in for service.

The STABILITY SYS ACTIVE message will appear on the Driver Information Center (DIC) only when the system is both on and activated. It means that an advanced computer-controlled system has come on to help your vehicle continue to go in the direction in which you're steering. StabiliTrak® activates when the computer senses that your vehicle is just starting to spin, as it might if you hit a patch of ice or other slippery spot on the road. When the system activates, you may hear a noise or feel a vibration in the brake pedal. This is normal. When the STABILITY SYS ACTIVE message is on, you should continue to steer in the direction you want to go. The system is designed to help you in bad weather or other difficult driving situations by making the most of whatever road conditions will permit. For more information on the stability messages, see Driver Information Center (DIC) .

StabiliTrak® and part of the traction control system can be turned off or back on by pressing the StabiliTrak® button located on the instrument panel.

When the system is turned off, the traction off light will illuminate, and the STABILITY SYS DISABLED message will appear on the DIC to warn the driver that both the stability system and part of the traction control system are disabled. Your vehicle will still have brake-traction control when StabiliTrak® is off, but will not be able to use the engine speed management system. See "Traction Control Operation" next for more information.

When the StabiliTrak® system has been turned off you may still hear system noises as a result of the brake-traction control coming on.

To limit wheel spin and realize the full benefits of the stability enhancement system, you should normally leave StabiliTrak® on, but it may be necessary to turn the system off if your vehicle is stuck in sand, mud, ice or snow, and you want to "rock" your 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 Your Vehicle is Stuck in Sand, Mud, Ice, or Snow .

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 you start your vehicle, and it will activate and display the TRACTION ACTIVE message in the Driver Information Center (DIC) if it senses that any of the wheels are spinning or beginning to lose traction while driving. If you turn off StabiliTrak®, only the brake-traction control portion of traction control will work. The engine speed management will be disabled. In this state, engine power is not reduced automatically and the driven wheels can spin more freely. This can cause the brake-traction control to activate constantly. For more information on the traction active message, see Driver Information Center (DIC) .

Notice: If the traction off light comes on due to heavy braking and/or because the traction control system has been continuously active, do not allow the wheel(s) of one axle to spin excessively. If you do, you may be causing damage to the transfer case. This could lead to costly repairs not covered by your warranty.

If the brake traction-control system activates constantly or if the brakes have heated up due to high-speed braking, brake traction-control will be disabled and the TRACTION SYS LIMITED message will be displayed. In the limited mode, the traction control system will only use engine traction-control and is limited in its ability to provide optimal performance since the system will not utilize brake traction-control to control slip on the drive wheels. The system will return to normal operation after the brakes have cooled. This can take up to two minutes or longer depending on brake usage.

Notice: If you allow the wheel(s) of one axle to spin excessively while the traction off, ABS and brake warning lights and the SERVICE STABILITY message are displayed, you could damage the transfer case. The repairs would not be covered by your warranty. Reduce engine power and do not spin the wheel(s) excessively while these lights and this message are displayed.

The traction control system may activate on dry or rough roads or under conditions such as heavy acceleration while turning or abrupt upshifts/downshifts of the transmission. When this happens you may notice a reduction in acceleration, or may hear a noise or vibration. This is normal.

If your vehicle is in cruise control when the system activates, the STABILITY SYS ACTIVE message will appear on the Driver Information Center and the cruise control will automatically disengage. When road conditions allow you to use cruise again, you may re-engage the cruise control. See Cruise Control .

StabiliTrak® may also turn off automatically if it determines that a problem exists with the system. If the problem does not clear itself after restarting the vehicle, you should see your dealer for service.

Adding non-GM accessories can affect your vehicle's performance. See Accessories and Modifications for more information.