
Maintain coolant concentration within
48% to 50%, which equates to a freeze
point between -30°F (-34°C) and -34°F
(-37°C). Check the coolant concentration
using a refractometer. We do not
recommend the use of hydrometers or
coolant test strips for measuring coolant
concentration.
Adding Coolant
WARNING: Do not add engine
coolant when the engine is hot. Failure
to follow this instruction could result in
personal injury. WARNING:
Do not remove the
coolant reservoir cap when the engine is
on or the cooling system is hot. Wait 10
minutes for the cooling system to cool
down. Cover the coolant reservoir cap
with a thick cloth to prevent the
possibility of scalding and slowly remove
the cap. Failure to follow this instruction
could result in personal injury.
Note: Automotive fluids are not
interchangeable. Do not use coolant or
windshield washer fluid outside of its
specified function and vehicle location.
Note: Do not use stop leak pellets, cooling
system sealants, or additives as they can
cause damage to the engine cooling or
heating systems. Resulting component
damage may not be covered by the vehicle
Warranty. It is very important to use prediluted
coolant approved to the correct
specification to avoid plugging the small
passageways in the engine cooling system.
See
Capacities and Specifications
(page 261). Do not mix different colors or
types of coolant in your vehicle. Mixing of
engine coolants or using an incorrect
coolant may harm the engine or cooling
system components and may not be
covered by the vehicle Warranty.
Note: Coolants marketed for all makes and
models may not be approved to our
specifications and may cause damage to
the cooling system. Resulting component
damage may not be covered by the vehicle
Warranty.
If the coolant level is at or below the
minimum mark, immediately add
prediluted coolant.
For vehicles with overflow coolant systems
with a non-pressurized cap on the coolant
recovery system, add coolant to the
coolant recovery reservoir when the engine
is cool. Add prediluted coolant to the
maximum level. For all vehicles which have
a coolant degas system with a pressurized
cap, or if it is necessary to remove the
coolant pressure relief cap on the radiator,
follow these steps to add engine coolant:
1. Turn the engine off and let it cool.
2. Slowly unscrew the cap. Any pressure escapes as you unscrew the cap.
3. Slowly fill the coolant reservoir with prediluted engine coolant to within the
minimum and maximum range on the
engine coolant reservoir. If you
removed the radiator cap in an
overflow system, fill the radiator until
the coolant is visible and the radiator
is almost full. If you add coolant to
bring the level within the minimum and
maximum range when the engine is not
cold, the system may remain under
filled.
197
F650750 (TBC) , enUSA, Edition date: 201804, Second-Printing Maintenance

Engine-driven Cooling Fan
Your vehicle may have an engine driven
cooling fan drive also called a fan clutch.
This fan drive changes the fan speed to
match the vehicle
’s changing cooling air
flow requirements. Fan speed, fan noise
level and fuel consumption all will increase
based on the driving conditions that
include trailer towing, hill climbing, heavy
loads, high speed and high ambient
temperature, individually or in combination.
The fan drive is designed to provide the
minimum fan speed and resulting
minimum fan noise and fuel consumption
required to meet the ever-changing vehicle
cooling air flow requirements. You can hear
the amount of fan noise increasing and
decreasing as the engine power
requirements and vehicle driving conditions
change as you drive. This is normal to the
operation of your vehicle. You may also
hear high levels of the fan when the engine
is first started and should normally
decrease after driving for a short time.
ENGINE COOLANT CHECK -
6.8L WARNING: Do not remove the
coolant reservoir cap when the engine is
on or the cooling system is hot. Wait 10
minutes for the cooling system to cool
down. Cover the coolant reservoir cap
with a thick cloth to prevent the
possibility of scalding and slowly remove
the cap. Failure to follow this instruction
could result in personal injury. WARNING:
Do not put coolant in
the windshield washer reservoir. If
sprayed on the windshield, coolant could
make it difficult to see through the
windshield. WARNING:
To reduce the risk of
personal injury, make sure the engine is
cool before unscrewing the coolant
pressure relief cap. The cooling system
is under pressure. Steam and hot liquid
can come out forcefully when you loosen
the cap slightly. WARNING:
Do not add coolant
further than the MAX mark.
When the engine is cold, check the
concentration and level of the coolant at
the intervals listed in the scheduled
maintenance information. See Scheduled
Maintenance
(page 322).
Note: Make sure that the coolant level is
between the
MIN and the MAX marks on
the coolant reservoir.
Note: Coolant expands when it is hot. The
level may extend beyond the
MAX mark.
Maintain coolant concentration within
48% to 50%, which equates to a freeze
point between -30°F (-34°C) and -34°F
(-37°C). Coolant concentration should be
checked using a refractometer. We
recommend Robinair® Coolant and
Battery Refractometer 75240 (Rotunda
tool part number: ROB75240). We do not
recommend the use of hydrometers or
coolant test strips for measuring coolant
concentration.
Note: Automotive fluids are not
interchangeable. Do not use coolant or
windshield washer fluid outside of its
specified function and vehicle location.
Note: Do not use stop leak pellets, cooling
system sealants, or additives as they can
cause damage to the engine cooling or
heating systems. Resulting component
damage may not be covered by the vehicle
Warranty.
200
F650750 (TBC) , enUSA, Edition date: 201804, Second-Printing Maintenance

Adding Coolant
WARNING: Do not remove the
coolant reservoir cap when the engine is
on or the cooling system is hot. Wait 10
minutes for the cooling system to cool
down. Cover the coolant reservoir cap
with a thick cloth to prevent the
possibility of scalding and slowly remove
the cap. Failure to follow this instruction
could result in personal injury.
It is very important to use prediluted
coolant meeting the correct specification
in order to avoid plugging the small
passageways in the engine cooling system.
See
Capacities and Specifications
(page 269). Incorrect prediluted coolant
use can cause damage not covered by the
vehicle Warranty.
If the coolant level is at or below the
minimum mark, add prediluted coolant
immediately.
To top up the coolant level do the
following:
1. Unscrew the cap slowly. Any pressure escapes as you unscrew the cap.
2. Add prediluted coolant meeting the correct specification. See
Scheduled
Maintenance (page 322).
3. Add enough prediluted coolant to reach the correct level.
4. Replace the coolant reservoir cap, turn
it clockwise until you feel a strong
resistance.
5. Check the coolant level in the coolant reservoir the next few times you drive
your vehicle. Do not mix different colors or types of
prediluted coolant in your vehicle. Mixing
of prediluted coolant or using an incorrect
prediluted coolant may harm the engine
or cooling system components and may
not be covered by the vehicle Warranty.
In case of emergency, you can add a large
amount of water without prediluted
coolant in order to reach a vehicle service
location. On arrival do the following:
1. Drain the cooling system.
2. Chemically clean the cooling system.
We recommend Motorcraft Premium
Cooling System Flush.
3. Refill with prediluted coolant as soon as possible.
Water alone, without prediluted coolant,
can cause engine damage from corrosion,
overheating or freezing.
Do not use the following as a coolant
substitute:
• Alcohol.
• Methanol.
• Brine.
• Any coolant mixed with alcohol or
methanol antifreeze.
Alcohol and other liquids can cause engine
damage from overheating or freezing.
Do not add extra inhibitors or additives to
the coolant. These can be harmful and
compromise the corrosion protection of
the coolant.
Recycled Coolant
We do not recommend the use of recycled
coolant as an approved recycling process
is not yet available.
Dispose of used engine coolant in an
appropriate manner. Follow your
community ’s regulations and standards
for recycling and disposing of automotive
fluids.
201
F650750 (TBC) , enUSA, Edition date: 201804, Second-Printing Maintenance

Severe Climates
If you drive in extremely cold climates:
•
It may be necessary to increase the
coolant concentration above 50%.
• A coolant concentration of 60%
provides improved freeze point
protection. Coolant concentrations
above 60% decrease the overheat
protection characteristics of the
coolant and may cause engine
damage.
If you drive in extremely hot climates:
• It may be necessary to decrease the
coolant concentration to 40%.
• A coolant concentration of 40%
provides improved overheat
protection. Coolant concentrations
below 40% decrease the freeze and
corrosion protection characteristics of
the coolant and may cause engine
damage.
Vehicles driven year-round in non-extreme
climates should use prediluted coolant for
optimum cooling system and engine
protection.
Fail-Safe Cooling
Fail-safe cooling allows you to temporarily
drive your vehicle before any incremental
component damage occurs. The fail-safe
distance depends on ambient
temperature, vehicle load and terrain.
How Fail-Safe Cooling Works
If the engine begins to overheat, the
coolant temperature gauge moves toward
the red zone: A warning lamp illuminates and
a message may appear in the
information display. If the engine reaches a preset
over-temperature condition, the engine
automatically switches to alternating
cylinder operation. Each disabled cylinder
acts as an air pump and cools the engine.
When this occurs, your vehicle still
operates, however:
•
Engine power is limited.
• The air conditioning system turns off.
Continued operation increases the engine
temperature, causing the engine to
completely shut down. Your steering and
braking effort increases in this situation.
When the engine temperature cools, you
can re-start the engine. Have your vehicle
checked as soon as possible to minimize
engine damage.
When Fail-Safe Mode Is Activated WARNING: Fail-safe mode is for
use during emergencies only. Operate
your vehicle in fail-safe mode only as
long as necessary to bring your vehicle
to rest in a safe location and seek
immediate repairs. When in fail-safe
mode, your vehicle will have limited
power, will not be able to maintain
high-speed operation, and may
completely shut down without warning,
potentially losing engine power, power
steering assist, and power brake assist,
which may increase the possibility of a
crash resulting in serious injury. WARNING:
Do not remove the
coolant reservoir cap when the engine is
on or the cooling system is hot. Wait 10
minutes for the cooling system to cool
down. Cover the coolant reservoir cap
with a thick cloth to prevent the
possibility of scalding and slowly remove
the cap. Failure to follow this instruction
could result in personal injury.
202
F650750 (TBC) , enUSA, Edition date: 201804, Second-Printing Maintenance

Your vehicle has limited engine power
when in the fail-safe mode, drive your
vehicle with caution. Your vehicle does not
maintain high-speed operation and the
engine may operate poorly.
Remember that the engine is capable of
automatically shutting down to prevent
engine damage. In this situation:
1. Pull off the road as soon as safely
possible and switch the engine off.
2. If you are a member of a roadside assistance program, we recommend
that you contact your roadside
assistance service provider.
3. If this is not possible, wait a short period for the engine to cool.
4. Check the coolant level. If the coolant level is at or below the minimum mark,
add prediluted coolant immediately.
5. When the engine temperature cools, you can re-start the engine. Have your
vehicle checked as soon as possible to
minimize engine damage.
Note: Driving your vehicle without repair
increases the chance of engine damage.
Engine Coolant Temperature
Management (If Equipped) WARNING:
To reduce the risk of
crash and injury, be prepared that the
vehicle speed may reduce and the
vehicle may not be able to accelerate
with full power until the coolant
temperature reduces.
If you tow a trailer with your vehicle, the
engine may temporarily reach a higher
temperature during severe operating
conditions, for example ascending a long
or steep grade in high ambient
temperatures. At this time, you may notice the coolant
temperature gauge moves toward the red
zone and a message may appear in the
information display.
You may notice a reduction in vehicle
speed caused by reduced engine power in
order to manage the engine coolant
temperature. Your vehicle may enter this
mode if certain high-temperature and
high-load conditions take place. The
amount of speed reduction depends on
vehicle loading, grade and ambient
temperature. If this occurs, there is no
need to pull off the road. You can continue
to drive your vehicle.
The air conditioning may automatically
turn on and off during severe operating
conditions to protect the engine from
overheating. When the coolant
temperature decreases to the normal
operating temperature, the air conditioning
turns on.
If the coolant temperature gauge moves
fully into the red zone, or if the coolant
temperature warning or service engine
soon messages appear in your information
display, do the following:
1. Pull off the road as soon as safely
possible and shift the transmission into
park (P).
2. Leave the engine running until the coolant temperature gauge needle
returns to the normal position. After
several minutes, if the temperature
does not drop, follow the remaining
steps.
3. Switch the engine off and wait for it to
cool. Check the coolant level.
4. If the coolant level is at or below the minimum mark, add prediluted coolant
immediately.
5. If the coolant level is normal, restart the engine and continue.
203
F650750 (TBC) , enUSA, Edition date: 201804, Second-Printing Maintenance

High Fluid Level
Do not add fluid further than the maximum
mark. Fluid levels above the maximum
mark may cause shift or engagement
concerns and possible damage.
Note:
High fluid levels can be caused by an
overheating condition.
Adding Transmission Fluid
Do not use supplemental transmission
fluid additives, treatments or cleaning
agents. The use of these materials may
affect transmission operation and result
in damage to internal transmission
components and could lead to
transmission damage that may not be
covered by the vehicle Warranty.
Use only recommended transmission fluid
that meets our specifications. See
Capacities and Specifications (page
261).
Note: Use of a non-approved automatic
transmission fluid may cause internal
transmission component damage.
If necessary, add fluid in
8 fl oz (250 ml)
increments through the filler tube until the
level is correct.
If an overfill occurs, excess fluid should be
removed, have your vehicle checked as
soon as possible. BRAKE FLUID CHECK WARNING:
Do not use any fluid
other than the recommended brake fluid
as this will reduce brake efficiency. Use
of incorrect fluid could result in the loss
of vehicle control, serious personal injury
or death. WARNING:
Only use brake fluid
from a sealed container. Contamination
with dirt, water, petroleum products or
other materials may result in brake
system damage or failure. Failure to
adhere to this warning could result in the
loss of vehicle control, serious personal
injury or death. WARNING:
Do not allow the fluid
to touch your skin or eyes. If this
happens, rinse the affected areas
immediately with plenty of water and
contact your physician. WARNING:
A fluid level between
the MAX and MIN lines is within the
normal operating range and there is no
need to add fluid. A fluid level not in the
normal operating range could
compromise the performance of the
system. Have your vehicle checked
immediately.
205
F650750 (TBC) , enUSA, Edition date: 201804, Second-Printing MaintenanceE163744

To avoid fluid contamination, the reservoir
cap must remain in place and fully tight,
unless you are adding fluid.
Only use fluid that meets Ford
specifications. See Capacities and
Specifications (page 255).
POWER STEERING FLUID
CHECK
Check the power steering fluid. See
Scheduled Maintenance
(page 322). If
adding fluid is necessary, use only
MERCON LV ATF
Check the fluid level when it is at ambient
temperature.
1. Check the fluid level in the reservoir. It should be between the MIN and MAX
range. Do not add fluid if the level is
within this range.
2. If the fluid level is low, add fluid to bring
the fluid level up to between the MIN
and MAX range.
3. Switch the engine on. 4.
While the engine idles, turn the steering
wheel left and right several times.
5. Switch the engine off.
6. Recheck the fluid level in the reservoir. Do not add fluid if the level is between
the MIN and MAX range.
7. If the fluid is low, add the proper type of fluid in small amounts, continuously
checking the level until it is between
the MIN and MAX range. See
Capacities and Specifications (page
261). Be sure to put the cap back on the
reservoir.
WASHER FLUID CHECK WARNING:
If you operate your
vehicle in temperatures below 40°F
(5°C), use washer fluid with antifreeze
protection. Failure to use washer fluid
with antifreeze protection in cold
weather could result in impaired
windshield vision and increase the risk
of injury or accident.
Add fluid to fill the reservoir if the level is
low. Only use a washer fluid that meets
Ford specifications. See
Capacities and
Specifications (page 255).
State or local regulations on volatile
organic compounds may restrict the use
of methanol, a common windshield washer
antifreeze additive. Washer fluids
containing non-methanol antifreeze
agents should be used only if they provide
cold weather protection without damaging
the vehicle ’s paint finish, wiper blades or
washer system.
206
F650750 (TBC) , enUSA, Edition date: 201804, Second-Printing MaintenanceE170684

DRAINING THE FUEL FILTER
WATER TRAP - 6.7L DIESEL
Your vehicle is equipped with a diesel fuel
conditioner module located on the
frame-rail under the driver-side floorboard
near the transmission.
You should drain water from the
module assembly whenever the
warning light comes on and the
message center directs you to drain the
water separator. This will occur when
approximately 8.45 fl oz (250 ml) of water
accumulates in the module. If you allow
the water level to exceed this level, the
water may pass through to the engine and
may cause fuel injection equipment
damage.
Draining the Diesel Fuel
Conditioner Module (DFCM) WARNING: Do not drain the
water-in-fuel separator while the engine
is running. Failure to follow this warning
may result in fire, serious injury, death or
property damage.
Note: If you drain the diesel fuel conditioner
module while the system is running air will
enter into the fuel system. The engine will
not operate properly if air enters the system.
Note: With fuel tank levels above 3⁄4 tank
it may be necessary to loosen the bowl three
turns before opening the drain. This will
actuate an anti-siphon valve at the fuel and
water separator inlet and prevent the fuel
from siphoning out of the tank.
Note: A loose drain valve can allow air to
enter the fuel system and cause drivetrain
issues. The engine will not operate properly.
Be sure that you fully tighten the drain valve.
1. Stop your vehicle and shut off the engine. 2. Locate the diesel fuel conditioner
module and place an appropriate
container under the drain port. 3.
Rotate the drain counterclockwise until
the O-ring is visible. Allow the diesel
fuel conditioner module to drain for
approximately 25 seconds or until
clean fuel is observed. Rotate the drain
clockwise to tighten it. If no liquid
drains, there may be a clog in the drain.
Have the conditioner module serviced
by an authorized dealer.
4. Make sure that you fully tighten the drain valve and then remove the
container from under your vehicle.
5. Restart the engine. If the Water in Fuel
Drain Filter
message and light
continues to illuminate, have the fuel
system checked and repaired.
FUEL FILTER - 6.8L
Your vehicle is equipped with a lifetime
fuel filter that is integrated with the fuel
tank. Regular maintenance or replacement
is not needed.
207
F650750 (TBC) , enUSA, Edition date: 201804, Second-Printing Maintenance E163360