and shifting procedures can be found in this 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 four–wheel drive models, the initial shift from two-wheel drive to
four–wheel drive while the vehicle is moving can cause some momentary
clunk and ratcheting sounds. This is the front drivetrain coming up to
speed and engaging the front wheels, 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.
Note:
If air is released from your tires, the Tire Pressure Monitoring
System (TPMS) indicator light may illuminate.
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.
If your vehicle is equipped with AdvanceTrac
威
with RSC, press the
AdvanceTrac
威
with RSC button (refer to
AdvanceTrac
威
with Roll
Stability Control (RSC) Stability Enhancement System
in this
chapter) while driving in deep sand if you experience excessive engine
power reduction.
Mud and water
If you must drive through high
water, drive slowly. Traction or
brake capability may be limited.
When driving through water,
determine the depth; avoid water
higher than the bottom of the hubs
(if possible) and proceed slowly. If the ignition system gets wet, the
vehicle may stall.
Once through water, always try the brakes. Wet brakes do not stop the
vehicle as effectively as dry brakes. Drying can be improved by moving
your vehicle slowly while applying light pressure on the brake pedal.
Be cautious of sudden changes in vehicle speed or direction when you
are driving in mud. Even four–wheel drive vehicles can lose traction in
2008 Expedition
(exd)
Owners Guide (post-2002-fmt)
USA
(fus)
Driving
296
