FORD 2004 Excursion v.1 - Manual (Page 172)

Parking
On some 4WD vehicles, when the transfer case is in the N (Neutral)
position, the engine and transmission are disconnected from the rest of
the driveline. Therefore, the vehicle is free to roll even if the automatic
transmission is in P (Park) or the manual transmission is in gear. Do not
leave the vehicle unattended with the transfer case in N (Neutral)
position. Always set the parking brake fully and turn off the ignition
when leaving the vehicle.
4WD Systems
4WD (when you select a 4WD mode), uses all four wheels to power the
vehicle. This increases traction, enabling you to drive over terrain and
road conditions that a conventional two-wheel drive vehicle can’t.
Power is supplied to all four wheels
through a transfer case. On 4WD
vehicles, the transfer case allows
you to select 4WD when necessary.
Information on transfer case
operation and shifting procedures
can be found in the Driving
chapter. Information on transfer
case maintenance can be found in the Maintenance and specifications
chapter. You should become thoroughly familiar with this information
before you operate your vehicle.
Normal characteristics
On some 4WD models, the initial shift from two-wheel drive to 4x4 while
the vehicle is moving can cause some momentary clunk and ratcheting
sounds. This is the front drivetrain coming up to speed and the
automatic locking hubs engaging and is not cause for concern.
Sand
When driving over sand, try to keep all four wheels on the most solid
area of the trail. Avoid reducing the tire pressures but shift to a lower
gear and drive steadily through the terrain. Apply the accelerator slowly
and avoid spinning the wheels.
If you must reduce the tire pressure for whatever reason in sand, make
sure you re-inflate the tires as soon as possible.
Avoid excessive speed because vehicle momentum can work against you
and cause the vehicle to become stuck to the point that assistance may
be required from another vehicle. Remember, you may be able to back
out the way you came if you proceed with caution.
Driving
172