Jeep 2014 Grand Cherokee Owner's Manual page 416

414 STARTING AND OPERATING
This transfer case is fully automatic in the 4WD HI mode.
When additional traction is required, the 4WD LOW
position can be used to lock the front and rear driveshafts
together and force the front and rear wheels to rotate at
the same speed. The 4WD LOW position is intended for
loose, slippery road surfaces only. Driving in the 4WD
LOW position on dry, hard-surfaced roads may cause
increased tire wear and damage to driveline components.
When operating your vehicle in 4WD LOW, the engine
speed is approximately three times that of the 4WD HI
position at a given road speed. Take care not to overspeed
the engine and do not exceed 25 mph (40 km/h).
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.
WARNING!
You or others could be injured if you leave the
vehicle unattended with the transfer case in the
NEUTRAL (N) position without first fully engaging
the parking brake. The transfer case NEUTRAL (N)
position disengages both the front and rear drive
shafts 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.