Shifting between Control Trac system modes
Press any button (4X2, 4X4 AUTO or 4X4) at any forward speed. The
message center may display4X4 SHIFT IN PROGRESSduring the
system shift. The message center will then display “4X4 AUTO” if 4X4
AUTO is selected or “4X4” if 4X4 is selected. The message center will
momentarily display “4X2” if 4X2 is selected
Note:Some noise may be heard as the system shifts or engages.
Driving off-road with truck and utility vehicles
Four–wheel drive vehicles are specially equipped for driving on sand,
snow, mud and rough terrain and have operating characteristics that are
somewhat different from conventional vehicles, both on and off the road.
The AdvanceTracwith RSC stability enhancement system can be turned
off manually by pressing the AdvanceTracwith RSC button (refer to
AdvanceTracwith Roll Stability Control (RSC) Stability
Enhancement Systemin this chapter) while operating in 4X2, 4X4
AUTO or 4X4 while driving in deep sand, very deep snow or more
strenuous off-road maneuvers. This will disable the engine management
feature, allowing the vehicle to maintain full power and enhanced
momentum through the obstacle.
How your vehicle differs from other vehicles
Truck and utility vehicles can differ from some other vehicles. Your
vehicle may be higher to allow it to travel over rough terrain without
getting hung up or damaging underbody components.
The differences that make your vehicle so versatile also make it handle
differently than an ordinary passenger car.
Maintain steering wheel control at all times, especially in rough terrain.
Since sudden changes in terrain can result in abrupt steering wheel
motion, make sure you grip the steering wheel from the outside. Do not
grip the spokes.
Drive cautiously to avoid vehicle damage from concealed objects such as
rocks and stumps.
You should either know the terrain or examine maps of the area before
driving. Map out your route before driving in the area. To maintain
steering and braking control of your vehicle, you must have all four
wheels on the ground and they must be rolling, not sliding or spinning.
Driving
255
2012 Navigator(nav)
Owners Guide, 1st Printing
USA(fus)
If your vehicle gets stuck
If your vehicle gets stuck in mud or snow it may be rocked out by
shifting between forward and reverse gears, stopping between shifts, in a
steady pattern. Press lightly on the accelerator in each gear.
Do not rock the vehicle if the engine is not at normal operating
temperature or damage to the transmission may occur.
Do not rock the vehicle for more than a few minutes or damage
to the transmission and tires may occur or the engine may
overheat.
WARNING:Always set the parking brake fully and make sure
the gearshift is latched in P (Park). Turn the ignition to the
LOCK position and remove the key whenever you leave your vehicle.
WARNING:If the parking brake is fully released, but the brake
warning lamp remains illuminated, the brakes may not be
working properly. See your authorized dealer.
WARNING:Do not spin the wheels at over 35 mph (56 km/h).
The tires may fail and injure a passenger or bystander.
Emergency maneuvers
•In an unavoidable emergency situation where a sudden sharp turn
must be made, remember to avoid “over-driving” your vehicle, i.e.,
turn the steering wheel only as rapidly and as far as required to avoid
the emergency. Excessive steering will result in less vehicle control,
not more. Additionally, smooth variations of the accelerator and/or
brake pedal pressure should be utilized if changes in vehicle speed are
called for. Avoid abrupt steering, acceleration or braking which could
result in an increased risk of loss of vehicle control, vehicle rollover
and/or personal injury. Use all available road surface to return the
vehicle to a safe direction of travel.
•In the event of an emergency stop, avoid skidding the tires and do not
attempt any sharp steering wheel movements.
Driving
257
2012 Navigator(nav)
Owners Guide, 1st Printing
USA(fus)
WARNING:Vehicles with a higher center of gravity such as
utility and four-wheel drive vehicles handle differently than
vehicles with a lower center of gravity. Utility and four-wheel drive
vehicles arenotdesigned for cornering at speeds as high as passenger
cars any more than low-slung sports cars are designed to perform
satisfactorily under off-road conditions. Avoid sharp turns, excessive
speed and abrupt maneuvers in these vehicles. Failure to drive
cautiously could result in an increased risk of loss of vehicle control,
vehicle rollover, personal injury and death.
•If the vehicle goes from one type of surface to another (i.e., from
concrete to gravel) there will be a change in the way the vehicle
responds to a maneuver (steering, acceleration or braking). Again,
avoid these abrupt inputs.
Control Tracfour–wheel drive system (if equipped)
When a four–wheel drive mode is selected, the Control Trac system 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 cannot.
Power is supplied to all four wheels through a transfer case. On
four–wheel drive vehicles, the transfer case allows you to select
four–wheel drive when necessary. Information on transfer case operation
and shifting procedures can be found in this chapter. Information on
transfer case maintenance can be found in theMaintenance and
Specificationschapter. 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.
Driving
258
2012 Navigator(nav)
Owners Guide, 1st Printing
USA(fus)
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 AdvanceTracwith RSC, press the
AdvanceTracwith RSC button (refer toAdvanceTracwith Roll
Stability Control (RSC) Stability Enhancement Systemin 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
slick mud. As when you are driving over sand, apply the accelerator
slowly and avoid spinning your wheels. If the vehicle does slide, steer in
the direction of the slide until you regain control of the vehicle.
If the transmission, transfer case, front axle or rear axle are submerged
in water, their fluids should be checked and changed, if necessary.
Driving through deep water may damage the transmission.
If the front or rear axle is submerged in water, the axle lubricant should
be replaced.
After driving through mud, clean off residue stuck to rotating driveshafts
and tires. Excess mud stuck on tires and rotating driveshafts causes an
imbalance that could damage drive components.
Driving
259
2012 Navigator(nav)
Owners Guide, 1st Printing
USA(fus)
Descend a hill in the same gear you
would use to climb up the hill to
avoid excessive brake application
and brake overheating. Do not
descend in neutral; instead,
disengage overdrive or manually
shift to a lower gear. When
descending a steep hill, avoid
sudden hard braking as you could
lose control. When you brake hard,
the front wheels can’t turn and if
they aren’t turning, you won’t be
able to steer. The front wheels have to be turning in order to steer the
vehicle. Rapid pumping of the brake pedal will help you slow the vehicle
and still maintain steering control.
If your vehicle has anti-lock brakes, apply the brakes steadily. Do not
“pump” the brakes.
Driving on snow and ice
Four–wheel drive vehicles have advantages over two–wheel drive
vehicles in snow and ice but can skid like any other vehicle.
Should you start to slide while driving on snowy or icy roads, turn the
steering wheel in the direction of the slide until you regain control.
Avoid sudden applications of power and quick changes of direction on
snow and ice. Apply the accelerator slowly and steadily when starting
from a full stop.
Avoid sudden braking as well. Although a four–wheel drive vehicle may
accelerate better than a two-wheel drive vehicle in snow and ice, it won’t
stop any faster, because as in other vehicles, braking occurs at all four
wheels. Do not become overconfident as to road conditions.
Make sure you allow sufficient distance between you and other vehicles
for stopping. Drive slower than usual and consider using one of the lower
gears. In emergency stopping situations, apply the brake forcefully and
steadily. Do not “pump” the brakes. Refer to theBrakessection of this
chapter for additional information on the operation of the anti-lock brake
system.
Driving
261
2012 Navigator(nav)
Owners Guide, 1st Printing
USA(fus)
Tire change procedure
WARNING:To help prevent the vehicle from moving when you
change a tire, be sure the parking brake is set, then block the
wheels (both front or both rear) on the opposite end of the vehicle
from the wheel being changed. If on a grade, block both opposite
wheels on the downward side of the hill.
WARNING:If the vehicle slips off the jack, you or someone else
could be seriously injured.
WARNING:On vehicles equipped with air suspension, turn off
the air suspension system prior to jacking, hoisting or towing
your vehicle.
WARNING:Turn off the running boards (if equipped) before
jacking or placing any object under the vehicle. Never place your
hand between the extended running board and the vehicle. A moving
running board may cause injury.
WARNING:Do not attempt to change a tire on the side of the
vehicle close to moving traffic. Pull far enough off the road to
avoid the danger of being hit when operating the jack and changing the
wheel.
Note:Passengers should not remain in the vehicle when the vehicle is
being jacked.
If your vehicle is equipped with air suspension, refer toMessage center
in theInstrument Clusterchapter for instructions on turning the air
suspension system off.
Refer to the instruction sheet (located in the rear floor compartment
behind the 3rd row seat with the jack tray tools assembly kit) for
detailed tire change instructions.
Roadside Emergencies
279
2012 Navigator(nav)
Owners Guide, 1st Printing
USA(fus)
1. Block the wheels (both front or
both rear) on the opposite end of
the vehicle from the wheel being
changed. If on a grade, block both
wheels on the downward side of the
hill.
2. Turn off the air suspension system. The air suspension system is
controlled through the message center. Refer toAir suspension system
in theDrivingsection for more information. Also, turn off the
deployable running boards (if equipped). Refer toMessage centerin the
Instrument Clustersection.
3. Obtain the spare tire and jack from their storage locations.
4. Use the tip of the jack handle to
remove any wheel trim. Loosen each
wheel lug nut one-half turn
counterclockwise but do not remove
them until the wheel is raised off
the ground.
5. Position the jack according to the
jack locator arrows found on the
frame and turn the jack handle and
extension tool assembly clockwise.
Note:Use the frame rail as the
jacking point, NOT the control arm.
6. Lift the vehicle so the tire is no
further than 1 inch (2.5 cm) off the
ground when installing the spare tire.
Roadside Emergencies
280
2012 Navigator(nav)
Owners Guide, 1st Printing
USA(fus)
WARNING:When one of the rear wheels is off the ground, the
transmission alone will not prevent the vehicle from moving or
slipping off the jack, even if the transmission is in P (Park). To prevent
the vehicle from moving when you change the tire, be sure that the
parking brake is set and the block the wheels (both front or both rear)
on the opposite end of the vehicle from the wheel being changed. If on
a grade, block both opposite wheels on the downward side of the hill.
If the vehicle slips off the jack, someone could be seriously injured.
•Front
•Rear
WARNING:Turn off the running boards (if equipped) before
jacking or placing any object under the vehicle. Never place your
hand between the extended running board and the vehicle. A moving
running board may cause injury.
Roadside Emergencies
281
2012 Navigator(nav)
Owners Guide, 1st Printing
USA(fus)