2021 FORD F-450 tow

5. Remove the clips that secure the air
filter housing cover. Push the air filter
cover toward the center of the vehicle
and up slightly to release it.
6. Remove the air filter element from the
air filter housing.
7. Install the new air filter element.
8. Engage the clips to secure the air filter housing cover to the air filter housing.
Be careful not to crimp the filter
element edges between the air filter
housing and cover. Ensure that you
align the tabs on the edge properly into
the slots.
9. Slip the air tube onto the air filter housing and tighten the air-tube clamp
bolt snugly. Do not over tighten
air-tube clamp bolt. 10. Reconnect the mass air flow sensor
electrical connector to the outlet
tube. Make sure the locking tab on
the connector is in the locked
position.
DRAINING THE FUEL FILTER
WATER TRAP - 6.7L DIESEL WARNING: Do not dispose of fuel
in the household refuse or the public
sewage system. Use an authorized waste
disposal facility.
Your vehicle has a diesel fuel conditioner
module. The module is mounted between
the outboard side of the fuel tank and the
frame rail.
Note: The module is at the front of the fuel
tank or at the front of the aft-axle fuel tank
on some models.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- MaintenanceE207259
x3 E163760

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.
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.
366
Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Maintenance

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.
367
Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-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:
• You can decrease the coolant
concentration to 40%.
• 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 engine
coolant for optimum cooling system and
engine protection.
Coolant Change
Follow the specific mileage intervals, as
listed in the scheduled maintenance
information, to change the coolant. The
information display may display a message
to change coolant at this time. Add
prediluted coolant approved to the correct
specification. See Capacities and
Specifications (page 441). 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 -
7.3L 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.
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Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Maintenance

Dispose of used engine coolant in an
appropriate manner. Follow your
community
’s regulations and standards
for recycling and disposing of automotive
fluids.
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:
• You can decrease the coolant
concentration to 40%.
• 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 engine
coolant for optimum cooling system and
engine protection.
Coolant Change
Change the coolant at specific mileage
intervals as listed in the scheduled
maintenance information. The information
display may display a message to change
coolant at this time. Add prediluted
coolant approved to the correct
specification. See Capacities and
Specifications (page 441). Engine-driven Cooling Fan (Fan
Clutch)
Your vehicle comes with 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 will hear
the amount of fan noise increasing and
decreasing as the engine power
requirements and vehicle driving conditions
change as you drive. This is to be expected
as being normal to the operation of your
vehicle. High levels of fan noise might also
be heard when your engine is first started,
and should normally decrease after driving
for a short time.
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.
374
Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Maintenance

If the engine reaches a preset
over-temperature condition, the engine
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. 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
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.
375
Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Maintenance

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 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. AUTOMATIC TRANSMISSION
FLUID CHECK
Note:
Transmission fluid should be checked
by an authorized dealer. If required, fluid
should be added by an authorized dealer.
The automatic transmission does not have
a transmission fluid dipstick.
Have an authorized dealer check and
change the transmission fluid and filter at
the correct service interval. See your
scheduled maintenance information. Your
transmission does not consume fluid.
However, the fluid level should be checked
if the transmission is not working properly,
(i.e., if the transmission slips or shifts
slowly) or if you notice some sign of fluid
leakage.
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.
376
Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- Maintenance

3. Drain the diesel fuel conditioner
module. Turn the drain plug
counterclockwise until it stops. Do not
use any tools to loosen the drain plug.
Drain the filter, approximately 0.53 gal
(2 L), into an appropriate container.
Do not re-use the fuel drained from the
module. 4. Disconnect the electrical connector.
5. Fully loosen the bolts securing the
lower portion of the diesel fuel
conditioner module housing.
Note: Do not fully remove the bolts from
the lower portion of the diesel fuel
conditioner module housing.
6. Remove the lower portion of the diesel
fuel conditioner module housing. 7. Slide the filter element toward the
drain plug to disengage the securing
clips.
Installation
1. Slide the filter element into the housing
and fully engage the securing clips.
2. Install the lower portion of the housing.
Tighten the bolts until you feel a strong
resistance. Maximum torque
7 lb.ft
(9 Nm).
3. Connect the electrical connector.
4. Tighten the drain plug, turn it clockwise
until it stops and you feel a strong
resistance. Do not use any tools to
tighten the drain plug.
388
Super Duty (TFE) Canada/United States of America, enUSA, Edition date: 202008, Third-Printing- MaintenanceE269861 E269862 E269863