2010 GMC Sierra 1500 Crew Cab Owner's Manual - Page 381

Let us say the road is wet and you are driving safely. Suddenly, an animal jumps out in front of you. You slam on the brakes and continue braking. Here is what happens with ABS: A computer senses that the wheels are slowing down. If one of the wheels is about to stop rolling, the computer will separately work the brakes at each front wheel and at both rear wheels. ABS can change the brake pressure to each wheel, as required, faster than any driver could. This can help the driver steer around the obstacle while braking hard. As the brakes are applied, the computer keeps receiving updates on wheel speed and controls braking pressure accordingly. Remember: ABS does not change the time needed to get a foot up to the brake pedal or always decrease stopping distance. If you get too close to the vehicle in front of you, there will not be enough time to apply the brakes if that vehicle suddenly slows or stops. Always leave enough room up ahead to stop, even with ABS. Braking in Emergencies ABS allows the driver to steer and brake at the same time. In many emergencies, steering can help more than even the very best braking. Brake Assist (Except With 4.3L V6 Engine) If this vehicle has StabiliTrak®, it also has a Brake Assist feature designed to assist the driver in stopping or decreasing vehicle speed in emergency driving conditions. This feature uses the stability system hydraulic brake control module to supplement the power brake system under conditions where the driver has quickly and forcefully applied the brake pedal in an attempt to quickly stop or slow down the vehicle. The stability system hydraulic brake control module increases brake pressure at each corner of the vehicle until the ABS activates. Minor brake pedal pulsations or pedal movement during this time is normal and the driver should continue to apply the brake pedal as the driving situation dictates The Brake Assist feature will automatically disengage when the brake pedal is released or brake pedal pressure is quickly decreased. Using ABS Do not pump the brakes. Just hold the brake pedal down firmly and let antilock work. The brakes might vibrate or some noise might be heard, but this is normal. 5-5