2007 Dodge Nitro Owner's Manual - Page 250

250 STARTING AND OPERATING P (Park) This gear position supplements the parking brake by locking the transmission. The engine can be started in this range. Never use P (Park) while the vehicle is in motion. Apply the parking brake when leaving the vehicle in this range. Always apply parking brake first, then place the selector in P (Park) position. WARNING! It is dangerous to shift the selector lever out of P (Park) or N (Neutral) if the engine speed is higher than idle speed. If your foot is not firmly on the brake pedal, the vehicle could accelerate quickly forward or in reverse. You could lose control of the vehicle and hit someone or something. Only shift into gear when the engine is idling normally and when your right foot is firmly on the brake pedal. WARNING! Never use P (Park) position as a substitute for the parking brake. Always apply parking brake fully when parked to guard against vehicle movement and possible injury or damage.