2004 Jeep Grand Cherokee Owner's Manual - Page 188

188 STARTING AND OPERATING Proper operation of four wheel drive vehicles depends on tires of equal size, type, and circumference on each wheel. Any difference will adversely affect shifting and cause damage to the transfer case. Because four wheel drive provides improved traction, there is a tendency to exceed safe turning and stopping speeds. Do not go faster than road conditions permit. Shift Positions For additional information on the appropriate use of each transfer case mode position, see the information below: 2WD Rear Wheel Drive High Range - Normal street and highway driving. Dry hard surfaced roads. 4 PART TIME Part Time 4 Wheel Drive High Range - Locks the transfer case inter-axle differential. Forces the front and rear wheels to rotate at the same speed. Additional traction for loose, slippery road surfaces only. 4 FULL TIME Full Time 4 Wheel Drive High Range - Employs interaxle differential. Allows front and rear wheels to rotate at different speeds. All roads surfaces. WARNING! You or others could be injured if you leave the vehicle unattended with the transfer case in the N (Neutral) position without first fully engaging the parking brake. The transfer case N (Neutral) position disengages both the front and rear driveshafts from the powertrain and will allow the vehicle to move regardless of the transmission position. The parking brake should always be applied when the driver is not in the vehicle.