axle maintenance FORD EXPLORER 2021 Owners Manual

PRINCIPLE OF OPERATION
This system is a proactive system. It has
the ability to anticipate wheel slip and
transfer torque to the front wheels before
slip occurs. Even when wheel slip is not
present, the system is continuously
adjusting to the torque distribution, in an
attempt to improve straight line and
cornering behavior, both on and off road.
The system automatically turns on every
time you switch the ignition on.
If any component requires maintenance,
a message appears in the information
display.
USING FOUR-WHEEL DRIVE
WARNING: Vehicles with a higher
center of gravity (utility and four-wheel
drive vehicles) handle differently than
vehicles with a lower center of gravity
(passenger cars). Avoid sharp turns,
excessive speed and abrupt steering in
these vehicles. Failure to drive cautiously
increases the risk of losing control of your
vehicle, vehicle rollover, personal injury
and death.
The intelligent 4WD system continuously
monitors vehicle conditions and adjusts
the power distribution between the front
and rear wheels. It combines transparent
all-surface operation with highly capable
four-wheel drive.
The 4WD system is always active and
requires no driver input. It is capable of
handling all road conditions including
street and highway driving as well as
off-road and winter driving. You can
optimize more 4WD control by selecting
different drive modes. See
Selecting a
Drive Mode (page 278). Note:
A warning message displays in the
information display when a 4WD system
fault is present. See
Information
Messages (page 121). A 4WD system fault
causes the 4WD system to default to
rear-wheel drive only mode. When this
warning message is displayed, have your
vehicle serviced at an authorized dealer.
Note: A warning message displays in the
information display if the 4WD system
overheats. See
Information Messages
(page 121). This condition could occur if the
vehicle is operated in extreme conditions
with excessive wheel slip, such as deep
sand. To resume normal 4WD function as
soon as possible, stop the vehicle in a safe
location and stop the engine for at least 10
minutes. After the engine is restarted and
the 4WD system is adequately cooled, the
warning message turns off and normal 4WD
function returns.
Operating Four-Wheel Drive (4WD)
Vehicles With Spare Tires
Do not use a different size spare tire other
than the tire provided. If the mini-spare tire
is installed, the 4WD system will disable
and enter rear-wheel drive only mode to
protect driveline components. Some
limited 4WD traction could be provided if
the mini-spare is installed on one of the
front wheels. If you are in driving conditions
where limited 4WD traction is needed
while the mini-spare is installed, it is
recommended the mini-spare be installed
on the front axle.
See Information
Messages (page 121).
If the mini-spare is installed, this condition
is indicated by a warning in the information
display. If there is a warning message in
the information display from using the
spare tire, this indicator should turn off
after reinstalling or replacing the normal
road tire and cycling the ignition off and
on. We recommended reinstalling or
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(If Equipped)

replacing the normal road tire as soon as
possible. Major dissimilar tire sizes
between the front and rear axles could
cause the 4WD system to stop functioning
and default to rear-wheel drive or damage
the 4WD system.
The slip response system could activate if
the mini spare is installed on the front
wheels. If the mini spare was installed on
the rear wheels the slip response system
will fully disable. In situations where there
is a wintery mix or an off road situation,
and you need to use a mini spare, you must
install the mini spare in the front tire
position and move a full size tire to the rear
tire position for the slip response system
to function.
Operating Four-Wheel drive (4WD)
Vehicles with Mismatched Tires
WARNING: Only use replacement
tires and wheels that are the same size,
load index, speed rating 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 (affixed
to either the door hinge pillar, door-latch
post, or the door edge that meets the
door-latch post, next to the driver's
seating position), 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
contact your authorized dealer as soon
as possible. 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. Major dissimilar tire sizes between the front
and rear axles (for example, 17 inch low
profile tires on the front axle and 22 inch
high profile tires on the rear axle) could
cause the 4WD system to stop functioning
and default to rear-wheel drive or damage
the 4WD system.
For optimum 4WD Performance, it is
recommended to follow the tire rotation
maintenance schedule. To avoid potential
4WD malfunction or 4WD system damage,
it is recommended to replace all four tires
rather than mixing significantly worn tires
with new tires. For example, using 3 worn
tread tires and 1 new tread tire all of the
same original tire size/brand, can be
tolerated by the 4WD system as long as
the worn tires still have usable tread depth.
How Your Vehicle Differs from
Other Vehicles
Truck and utility vehicles can differ from
some other vehicles. Your vehicle could 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.
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(If Equipped)

ESSENTIAL TOWING CHECKS
Follow these guidelines for safe towing:
•
Do not tow a trailer until you drive your
vehicle at least 1,000 mi (1,600 km).
• Consult your local motor vehicle laws
for towing a trailer.
• See the instructions included with
towing accessories for the proper
installation and adjustment
specifications.
• Service your vehicle more frequently if
you tow a trailer.
See Scheduled
Maintenance (page 482).
• If you use a rental trailer, follow the
instructions the rental agency gives
you.
You can find information on load
specification terms found on the tire label
and Safety Compliance label as well as
instructions on calculating your vehicle's
load in the Load Carrying chapter.
See
Load Limit (page 282).
Remember to account for the trailer
tongue weight as part of your vehicle load
when calculating the total vehicle weight.
Hitches
Do not use a hitch that either clamps onto
the bumper or attaches to the axle.
Distribute the trailer load so 10-15% of the
total trailer weight is on the tongue.
A weight distributing hitch is not required
for your vehicle.
Safety Chains
Note: Do not attach safety chains to the
bumper.
Always connect the safety chains to the
hook retainers of your vehicle hitch. To connect the trailer
’s safety chains, cross
them under the trailer tongue and allow
enough slack for turning tight corners. Do
not allow the chains to drag on the ground.
Trailer Brakes WARNING:
Do not connect a
trailer's hydraulic brake system directly
to your vehicle's brake system. Your
vehicle may not have enough braking
power and your chances of having a
collision greatly increase.
Electric brakes and manual, automatic or
surge-type trailer brakes are safe if you
install them properly and adjust them to
the manufacturer's specifications. The
trailer brakes must meet local and federal
regulations.
The rating for the tow vehicle's braking
system operation is at the gross vehicle
weight rating, not the gross combined
weight rating.
Safe control of towed vehicles requires
separate functioning brake systems for
vehicles and trailers weighing more than
1,500 lb (680 kg)
when loaded.
Trailer Lamps WARNING:
Never connect any
trailer lamp wiring to the vehicle's tail
lamp wiring; this may damage the
electrical system resulting in fire. Contact
your authorized dealer as soon as
possible for assistance in proper trailer
tow wiring installation. Additional
electrical equipment may be required.
Most towed vehicles require trailer lamps.
Make sure all running lights, brake lights,
direction indicators and hazard flashers
are working.
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Utility vehicles and trucks handle
differently than passenger cars in the
various driving conditions that are
encountered on streets, highways and
off-road. Utility vehicles and trucks are not
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.
Study your owner's manual and any
supplements for specific information about
equipment features, instructions for safe
driving and additional precautions to
reduce the risk of an accident or serious
injury.
Four-Wheel Drive system (if
equipped)
WARNING: Do not become
overconfident in the ability of four-wheel
drive vehicles. Although a four-wheel
drive vehicle may accelerate better than
a 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.
A vehicle equipped with Four-Wheel Drive
has the ability to use all four wheels to
power itself. This increases traction which
may enable you to safely 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. Four-wheel drive vehicles
allow you to select different modes as
necessary. You can find more information
on transfer case operation, drive mode
selection, and transfer case maintenance
in this manual. See
Four-Wheel Drive
(page 207). You should become thoroughly
familiar with this information before you
operate your vehicle. We recommend installing the temporary
spare wheel and tire on the front axle when
possible. This could provide limited 4WD
traction.
Four-wheel drive: Never use a spare tire of
a different size than the one provided with
your vehicle. This could cause the
four-wheel drive system to default to
rear-wheel drive.
How your vehicle differs from
other vehicles
Sport utility vehicles 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.
• Narrower - to provide greater
maneuverability in tight spaces,
particularly in off-road use.
As a result of the above dimensional
differences, sport utility vehicles and trucks
often have a higher center of gravity and a
greater difference in center of gravity
between the loaded and unloaded
condition. These differences that make
your vehicle so versatile also make it
handle differently than an ordinary
passenger car.
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When to Expect the OIL CHANGE REQUIRED Message
Vehicle Use and Example
Interval 1
Normal
7,500– 10,000 mi
(12,000– 16,000 km) Normal commuting with highway driving
No, or moderate, load or towing
Flat to moderately hilly roads
No extended idling
Severe
5,000– 7,500 mi
(8,000– 12,000 km) Moderate to heavy load or towing
Mountainous or off-road conditions
Extended idling
Extended hot or cold operation
Extreme
3,000–5,000 mi
(4,800–8,000 km) Maximum load or towing
Extreme hot or cold operation
Extended engine idling
1 Hybrid vehicles may achieve longer distances between oil changes, but do not exceed
the 1 year maximum oil change interval. Remaining oil life can be accessed through the
information display. See Information Displays (page 112).
Normal Maintenance Intervals At Every Oil Change Interval as Indicated by the Information Display
1
Change the engine oil and filter. 2
Rotate the tires.
Perform a multi-point inspection, recommended.
Inspect the brake pads, rotors, hoses and parking brake.
Inspect the engine cooling system strength and hoses.
Inspect the exhaust system and heat shields.
Inspect the front axle.
Inspect the rear axle and U-joints.
Inspect the half-shaft boots.
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Other Maintenance Items
1
Change the automatic transmission fluid.
Every 150,000 mi
(240,000 km) Replace the accessory drive belt or belts. 4
1 Perform these maintenance items within
3,000 mi (4,800 km) of the last engine oil
and filter change. Do not exceed the designated distance for the interval.
2 Initial replacement at 10 years or
200,000 mi (322,000 km), then every 5 years or
100,000 mi (160,000 km).
3 After initial inspection, inspect every other oil change until replaced.
4 If not replaced within the last
100,000 mi (160,000 km).
SPECIAL OPERATING
CONDITIONS SCHEDULED
MAINTENANCE
If you operate your vehicle primarily in any
of the following conditions, you need to
perform extra maintenance as indicated.
If you operate your vehicle occasionally
under any of these conditions, it is not
necessary to perform the extra
maintenance. For specific
recommendations, see your dealership
service advisor or technician. Perform the services shown in the
following tables when specified or within
3,000 mi (4,800 km)
of the message
appearing in the information display
prompting you to change your oil.
• Example 1: The message comes on at
28,750 mi (46,270 km)
. Perform the
30,000 mi (48,000 km) automatic
transmission fluid replacement.
• Example 2: The message has not come
on, but the odometer reads 30,000 mi
(48,000 km)
(for example, the
Intelligent Oil-Life Monitor was reset
at
25,000 mi (40,000 km). Perform
the engine air filter replacement. Towing a Trailer or Using a Car-top Carrier
Change engine oil and filter as indicated by the information
display and perform services listed in the Normal Sched-
uled Maintenance chart.
As required
Inspect front axle.
Inspect frequently, service
as required
Inspect rear axle and U-joints.
Inspect half-shaft boots.
See axle maintenance items under Exceptions.
Replace spark plugs.
Every
60,000 mi
(96,000 km)
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Extensive Idling or Low-speed Driving for Long Distances, as in Heavy Commercial Use
Change engine oil and filter as indicated by the information
display and perform services listed in the Normal Sched-
uled Maintenance chart.
As required
Replace cabin air filter.
Inspect frequently, service
as required
Replace engine air filter.
Replace spark plugs.
Every 60,000 mi
(96,000 km) Operating in Dusty or Sandy Conditions - Such as Unpaved or Dusty Roads
Replace cabin air filter.
Inspect frequently, service
as required
Replace engine air filter.
Inspect the wheels and related components for abnormal
noise, wear, looseness or drag.
Every
5,000 mi (8,000 km)
Rotate tires, inspect tires for wear and measure tread
depth.
Change engine oil and filter. 1
Every
5,000 mi (8,000 km)
or six months
Perform multi-point inspection.
1 Reset your Intelligent Oil-Life Monitor after engine oil and filter changes. See Oil Change
Indicator Reset
(page 327). Exclusive use of E85 - Flex Fuel Vehicles Only
If ran exclusively on E85, fill the fuel tank full with regular
unleaded fuel.
Every oil change
Exceptions
There are several exceptions to the Normal
Schedule: Axle and Transfer Case Maintenance
The transfer case, front and rear axles in
your vehicle do not require normal
scheduled maintenance. Your vehicle is
electronically monitored and notifies you
of required service by displaying a message
in the information display. The transfer
case, front and rear axles are more likely
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to require a fluid change if the vehicle has
experienced extended periods of extreme
or severe duty cycle driving. Changing or
checking the transfer case, front and/or
rear axle lubricant is not necessary unless
the unit has been submerged in water,
shows signs of leakage, a message
indicating required service displays.
Contact your authorized dealer for service.
California Fuel Filter Replacement
If you register your vehicle in California, the
California Air Resources Board has
determined that the failure to perform this
maintenance item does not nullify the
emission warranty or limit recall liability
before the completion of your vehicle's
useful life. Ford Motor Company, however,
urges you to have all recommended
maintenance services performed at the
specified intervals and to record all vehicle
service.
Hot Climate Oil Change Intervals
Vehicles operating in the Middle East,
North Africa, Sub-Saharan Africa or
locations with similar climates using an
American Petroleum Institute (API)
Certified for Gasoline Engines (Certification
mark) oil of SM or SN quality, the normal
oil change interval is 5,000 mi (8,000 km).
If the available API SM or SN oils are not
available, then the oil change interval is
3,000 mi (4,800 km)
.
Engine Air Filter and Cabin Air Filter
Replacement
The life of the engine air filter and cabin air
filter is dependent on exposure to dusty
and dirty conditions. Vehicles operated in
these conditions require frequent
inspection and replacement of the engine
air filter and cabin air filter.
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