Power is supplied to all four wheels
through a transfer case or power
transfer unit. 4WD vehicles allow
you to select different drive modes
as necessary. Information on
transfer case operation and shifting
procedures can be found in the
Drivingchapter. 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.
On some 4WD models, the initial shift from two-wheel drive to 4WD
while the vehicle is moving can cause a momentary clunk and ratcheting
sound. These sounds are normal as the front drivetrain comes up to
speed and is not cause for concern.
Do not become overconfident in the ability of 4WD and AWD
vehicles. Although a 4WD or AWD vehicle may accelerate better
than two-wheel drive vehicle in low traction situations, it won’t stop
any faster than two-wheel drive vehicles. Always drive at a safe speed.
How your vehicle differs from other vehicles
SUV and trucks can differ from
some other vehicles in a few
noticeable ways. Your vehicle may
be:
•Higher – to allow higher load
carrying capacity and to allow it
to travel over rough terrain
without getting hung up or
damaging underbody components.
•Shorter – to give it the capability
to approach inclines and drive
over the crest of a hill without
getting hung up or damaging
underbody components. All other
things held equal, a shorter
wheelbase may make your vehicle
quicker to respond to steering inputs than a vehicle with a longer
wheelbase.
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Only use replacement tires and wheels that are the same size
and type (such as P-metric versus LT-metric or all-season versus
all-terrain) as those originally provided by Ford. The recommended tire
and wheel size may be found on either the Safety Compliance
Certification Label or the Tire Label which is located on the B-Pillar or
edge of the driver’s door. If this information is not found on these
labels then you should consult your Ford dealer. Use of any tire or
wheel not recommended by Ford can affect the safety and
performance of your vehicle, which could result in an increased risk of
loss of vehicle control, vehicle rollover, personal injury and death.
Additionally the use of non-recommended tires and wheels could cause
steering, suspension, axle or transfer case/power transfer unit failure. If
you have questions regarding tire replacement, see an authorized
dealer.
When mounting replacement tires and wheels, you should not
exceed the maximum pressure indicated on the sidewall of the
tire to set the beads without additional precautions listed below. If the
beads do not seat at the maximum pressure indicated, re-lubricate and
try again.
When inflating the tire for mounting pressures up to 20 psi greater
than the maximum pressure on the tire sidewall, the following
precautions must be taken to protect the person mounting the tire:
1. Make sure that you have the correct tire and wheel size.
2. Lubricate the tire bead and wheel bead seat area again.
3. Stand at a minimum of 12 feet away from the tire wheel assembly.
4. Use both eye and ear protection.
For a mounting pressure more than 20 psi greater than the maximum
pressure, a Ford Dealer or other tire service professional should do the
mounting.
Always inflate steel carcass tires with a remote air fill with the person
inflating standing at a minimum of 12 ft. away from the tire wheel
assembly.
Important:Remember to replace the wheel valve stems when the road
tires are replaced on your vehicle.
It is recommended that the two front tires or two rear tires generally be
replaced as a pair.
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CONTROL TRAC FOUR-WHEEL DRIVE (4X4) OPERATION
(IF EQUIPPED)
For important information regarding safe operation of this type
of vehicle, seePreparing to drive your vehiclein this chapter.
Do not use 4X4 mode on dry, hard surfaced roads. Doing so will produce
excessive noise, increase tire wear and may damage drive components.
4X4 mode is only intended for consistently slippery or loose surfaces.
Use of 4X4 mode on these surfaces may produce some noise (such as
occasional clunks) but will not damage drive components.
Your 4x4 features the heavy-duty Control Trac system which includes a
computer-operated transfer case. This unique system is interactive with
the road, continually monitoring and adjusting torque delivery to the
front and rear wheels to optimize vehicle control.
System indicator messages
The Control Trac system indicator messages display in the reconfigurable
telltale (RTT) location in the message center only under the following
conditions. If these messages display when driving in 4X2, contact your
authorized dealer as soon as possible. Refer toWarning lights and
chimesin theInstrument Clusterchapter.
•4X4 AUTO– displays when 4X4 AUTO is selected.
•4X4– displays when 4X4 is selected.
Positions of the Control Trac system
The Control Trac system functions
in three modes:
•4X2 (2WD)delivers power to
the rear wheels only. This is
appropriate for normal on-road
driving on dry pavement.
•4X4 AUTOprovides electronic
control four-wheel drive with power delivered to all four wheels, as
required, for increased traction. The RTT location in the message
center will display “4X4 AUTO” when this position is selected. This is
appropriate for all on-road driving conditions, such as dry road
surfaces, wet pavement, snow or gravel.
4X24X4
AUTO4X4
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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 arenot
designed 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 Trac four–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.
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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.
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Item Capacity Ford part numberFord part number /
Ford specification
Cooling system stop
leak pellets—Motorcraft Cooling
System Stop Leak PelletsVC-6 /
WSS-M99B37-B6
Engine oil 7.0 quarts (6.6 L)Motorcraft SAE 5W-20
Premium Synthetic
Blend Motor Oil
Motorcraft SAE 5W-20
Super Premium Motor
Oil
2
XO-5W20-QSP (US)
CXO-5W20- LSP12
(Canada) /
WSS-M2C930-A and API
Certification Mark
Automatic transmission
fluid
(6HP26)11.0 quarts
(10.5L)
3
Motorcraft MERCONSP
AT F
4
XT-6-QSP /
MERCONSP
Power steering fluidFill between MIN
and MAX lines on
reservoirMotorcraft MERCON
AT FXT-2-QDX /
MERCON
Front axle fluid (4X4)3.5-3.7 pints
(1.8-2.0L)Motorcraft SAE 80W-90
Premium Rear Axle LubeXY-80W90-QL /
WSP-M2C197-A
Rear axle
fluid–Conventional
differential
(9.75 inch axle)4.5 pints (2.13L)Motorcraft SAE 75W-140
Synthetic Rear Axle
Lube
5
XY-75W140-QL /
WSL-M2C192-A
Transfer case fluid
(4X4)2.0 quarts (1.9L)Motorcraft MERCON
AT FXT-2-QDX /
MERCON
2007 Navigator(nav)
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