2003 GMC Sierra 1500 Pickup Owner's Manual - Page 295

QUADRASTEERTM The QUADRASTEERTM System has a control and diagnostic module that monitors and records current system status and operational information. If your vehicle is equipped with the 4 Wheel Steer system it has the ability to steer the vehicle with all four wheels Once the 4 Wheel Steer mode is selected, it is recommended to leave the vehicle in this mode at all times, and during all driving and weather conditions. You can select this mode at any speed, however, if you are turning the system will not engage until the turn is complete. An emergency like this requires close attention and a quick decision. If you are holding the steering wheel at the recommended 9 and 3 o'clock positions, you can turn it a full 180 degrees very quickly without removing either hand. But you have to act fast, steer quickly, and just as quickly straighten the wheel once you have avoided the object. The fact that such emergency situations are always possible is a good reason to practice defensive driving at all times and wear safety belts properly. 4-14