FORD F-350 2021 Owners Manual

5.
Remove the air filter element from the
air filter housing.
6. Install in the reverse order.
CHANGING THE ENGINE AIR
FILTER - 6.7L DIESEL WARNING: To reduce the risk of
vehicle damage and personal burn
injuries, do not start your engine with the
air cleaner removed and do not remove
it while the engine is running.
Use the correct specification air filter
element. See
Motorcraft Parts (page
443).
Note: Failure to use the correct air filter
element may result in severe engine
damage. Resulting component damage
may not be covered by the vehicle Warranty.
Change the air filter element at the correct
service interval. See
Scheduled
Maintenance (page 565). 1. Disconnect the mass air flow sensor
electrical connector, if required.
2. Remove the clips (x3) that secure the air filter housing cover. Remove the air
filter housing cover. Disconnect and
pull the air intake tube away, as
needed. 3.
Remove the air filter element from the
air filter housing.
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4. Remove the auxiliary foam filter from
the air filter housing.
5. To install, reverse the removal procedure. The housing cover can be
oscillated slightly left to right to assist
with installation as needed, until
positioned such that all three clips can
be re-engaged.
Air Filter Restriction Gauge The air filter restriction gauge is in the
upper housing of the air filter assembly. Check the air filter restriction gauge
whenever you open the hood to carry out
general engine maintenance or at least
every 7,500 mi (12,000 km). If you operate
your vehicle in extremely dusty conditions,
check the gauge at least every 500 mi
(800 km) or two weeks, whichever occurs
first. Change the air filter element when
the restriction gauge reads near the
change filter line and the gauge is yellow.
Allowing the restriction gauge to reach
maximum affects engine performance and
fuel economy.
Operating your vehicle in heavy snowfall
or extreme rain conditions may allow
excessive amounts of snow or water into
the air intake system. This could restrict air
flow and cause the engine to lose power
or shut down.
After installing a new air filter element, you
must reset the gauge by pressing the reset
button.
After operating your vehicle during heavy
snowfall or extreme rain, do the following:
• Snow: At the earliest opportunity, open
the hood and clear any snow and ice
from the air filter housing inlet and
reset the air filter restriction gauge.
• Extreme rain: The air filter element
dries out after approximately 15– 30
minutes of driving at highway speeds.
At the earliest opportunity, open the
hood and reset the air filter restriction
gauge.
Note: Do not remove the foam filter.
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CHANGING THE ENGINE AIR
FILTER - 7.3L
WARNING: To reduce the risk of
vehicle damage and personal burn
injuries, do not start your engine with the
air cleaner removed and do not remove
it while the engine is running.
Note: Operating your vehicle in heavy
snowfall or extreme rain conditions may
allow excessive amounts of snow or water
into the air intake system. This could plug
or soak the air filter that could cause the
engine to lose power or shut down.
When replacing the air filter element, use
a Motorcraft® air filter element. See
Motorcraft Parts
(page 443).
Note: Failure to use the correct air filter
element may result in severe engine
damage. Resulting component damage
may not be covered by the vehicle Warranty.
Change the air filter element at the correct
interval. See
Scheduled Maintenance
(page 565). 1. Locate the mass air flow sensor
electrical connector on the air outlet
tube. Disconnect the mass air flow
sensor electrical connector. 2. Reposition the locking clip on the
connector, squeeze the connector and
pull it off of the air outlet tube. 3.
Clean the area from around the air tube
to the air cover connection to prevent
debris from entering the system. Next,
loosen the bolt on the air tube clamp
so the clamp is no longer snug to the
air tube. It is not necessary to
completely remove the clamp.
4. Pull the air tube off from the air cleaner
housing.
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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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You should drain water from the
module assembly whenever the
warning light illuminates or a
message appears in the information
display advising you to drain the water
separator. This occurs when approximately
6.76 fl oz (200 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.
Filter Location
Use the tables below to find the location
of your filter.
Pick-up Truck Filter Location
Box Length
Cab Type
Left side of fuel tank.
8 ft (2.4 m)
Regular.
6.75 ft (2.057 m)
SuperCab.
In front of fuel tank.
8 ft (2.4 m)
6.75 ft (2.057 m)
Super Crew Cab.
Left side of fuel tank.
8 ft (2.4 m)
Chassis Cab Filter Location
Fuel Tank Type
Cab Type
Right side of fuel tank.
Single midship fuel tank
Chassis Cab.
Right side of midship fueltank.
Aft axle/midship fuel tanks
Chassis Cab.
Front of fuel tank.
Single aft axle fuel tank
Chassis Cab.
Draining the Diesel Fuel
Conditioner Module
1. Switch the engine off.
2. Access the underside of your vehicle.
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3. Use the table to find the location of
your fuel filter. 4. 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 0.5 gal
(2 L), into an appropriate container.
Do not re-use the fuel drained from the
module.
5. 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.
6. Prime the system by turning the key to
the on position for 30 seconds. Turn
the key to the off position, then the on
position again for another 30 seconds.
Repeat this twice.
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ENGINE COOLANT CHECK -
6.2L
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 565).
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.
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
Cooling System Capacity and
Specification (page 456). 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.
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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 565).
3. Add enough prediluted coolant to reach the correct level.
4. Replace the coolant reservoir cap. Turn
the cap clockwise until it contacts the
hard stop.
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.
If you have to add more than
1.1 qt (1 L) of
engine coolant per month, have your
vehicle checked as soon as possible.
Operating an engine with a low level of
coolant can result in engine overheating
and possible engine damage.
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.
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.
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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.
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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.
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