2002 GMC Envoy Owner's Manual - Page 93

REVERSE (R): Use this gear to back up. NOTICE: Shifting to REVERSE (R) while the vehicle is moving forward could damage the transmission. Shift to REVERSE (R) only after the vehicle is stopped. To rock your vehicle back and forth to get out of snow, ice or sand without damaging your transmission, see "Stuck In Sand, Mud, Ice or Snow" in the Index. NEUTRAL (N): In this position, the engine doesn't connect with the wheels. To restart when you're already moving, use NEUTRAL (N) only. CAUTION: Shifting out of PARK (P) or NEUTRAL (N) while your engine is "racing" (running at high speed) is dangerous. Unless your foot is firmly on the brake pedal, your vehicle could move very rapidly. You could lose control and hit people or objects. Don't shift out of PARK (P) or NEUTRAL (N) while your engine is racing. NOTICE: Damage to your transmission caused by shifting out of PARK (P) or NEUTRAL (N) with the engine racing isn't covered by your warranty. 2-24