FORD F-350 2021 Owners Manual

1. Park your vehicle on a level surface.
2. Look at the brake fluid reservoir to see
where the brake fluid level is relative
to the MIN and the MAX marks on the
reservoir.
Note: If the brake fluid level is between the
MIN
and the MAX marks on the reservoir, it
is acceptable.
Note: If the brake fluid level is below the
MIN
mark or above the MAX mark, have
your vehicle checked as soon as possible.
Note: To avoid fluid contamination, the
reservoir cap must remain in place and fully
tight, unless you are adding fluid.
Only use fluid that meets our
specifications. See
Capacities and
Specifications (page 441).
Brake Fluid Service Interval
Brake fluid absorbs water over time which
degrades the effectiveness of the brake
fluid. Change the brake fluid at the
specified intervals to prevent degraded
braking performance. For detailed interval information, see
Scheduled Maintenance in your Owner's
Manual or your local maintenance guide.
POWER STEERING FLUID
CHECK
Check the power steering fluid. See
Scheduled Maintenance
(page 565). 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 fluid in small amounts, continuously checking the
level until it is between the MIN and
MAX range. For proper fluid type, See
Capacities and Specifications (page
441). Be sure to put the cap back on the
reservoir.
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CHANGING THE 12V BATTERY
WARNING: Batteries normally
produce explosive gases which can
cause personal injury. Therefore, do not
allow flames, sparks or lighted
substances to come near the battery.
When working near the battery, always
shield your face and protect your eyes.
Always provide correct ventilation. WARNING:
When lifting a
plastic-cased battery, excessive pressure
on the end walls could cause acid to flow
through the vent caps, resulting in
personal injury and damage to the
vehicle or battery. Lift the battery with a
battery carrier or with your hands on
opposite corners. WARNING:
Keep batteries out of
reach of children. Batteries contain
sulfuric acid. Avoid contact with skin,
eyes or clothing. Shield your eyes when
working near the battery to protect
against possible splashing of acid
solution. In case of acid contact with skin
or eyes, flush immediately with water for
a minimum of 15 minutes and get prompt
medical attention. If acid is swallowed,
call a physician immediately. WARNING:
Battery posts,
terminals and related accessories
contain lead and lead compounds,
chemicals known to the State of
California to cause cancer and
reproductive harm. Wash your hands
after handling
. WARNING:
This vehicle may have
more than one battery. Removing the
battery cables from only one battery
does not disconnect your vehicle
electrical system. Make sure you
disconnect the battery cables from all
batteries when disconnecting power.
Failure to do so may cause serious
personal injury or property damage.
Your vehicle is fitted with a Motorcraft
maintenance-free battery which normally
does not require additional water.
When a battery replacement is required,
you must use a recommended
replacement battery that matches the
electrical requirements of the vehicle.
Note: After cleaning or replacing the
battery, make sure you reinstall the battery
vent tube, battery cover or shield.
For longer, trouble-free operation, keep the
top of the battery clean and dry.
If you see any corrosion on the battery or
terminals, remove the cables from the
terminals and clean with a wire brush. You
can neutralize the acid with a solution of
baking soda and water.
Because your vehicle ’s engine is
electronically controlled by a computer,
some control conditions are maintained
by power from the battery. When the
battery is disconnected or a new battery
is installed, the engine must relearn its idle
and fuel trim strategy for optimum
driveability and performance. Flexible fuel
vehicles (FFV) must also relearn the
ethanol content of the fuel for optimum
driveability and performance.
To restore the settings, do the following:
1. Apply the parking brake.
2. Shift into park (P) or neutral (N).
3. Switch off all accessories.
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4. Press the brake pedal and start your
vehicle.
5. Run the engine until it reaches normal operating temperature. While the
engine is warming up, complete the
following: Reset the clock. Reset the
power windows bounce-back feature.
See Windows and Mirrors (page 95).
Reset the radio station presets. See
Audio System
(page 488).
6. Allow the engine to idle for at least one
minute.
7. Drive the vehicle at least 10 mi (16 km)
to completely relearn the idle trim and
fuel trim strategy.
Note: If you do not allow the engine to
relearn the idle and fuel trim strategy, the
idle quality of your vehicle may be adversely
affected until the engine computer
eventually relearns the idle trim and fuel
trim strategy.
Note: For flexible fuel vehicles, if you are
operating on E85, you may experience poor
starts or an inability to start the engine and
driveability problems until the fuel trim and
ethanol content have been relearned.
Make sure that you dispose of old batteries
in an environmentally friendly way. Seek
advice from your local authority about
recycling old batteries.
If storing your vehicle for more than 30
days without recharging the battery, we
recommend that you disconnect the
negative battery cable to maintain battery
charge for quick starting.
Battery Management System
(If
Equipped)
The battery management system monitors
battery conditions and takes actions to
extend battery life. If excessive battery
drain is detected, the system temporarily
disables some electrical systems to
protect the battery. Systems included are:
•
Heated rear window.
• Heated seats.
• Climate control.
• Heated steering wheel.
• Audio unit.
• Navigation system.
A message may appear in the information
displays to alert you that battery
protection actions are active. These
messages are only for notification that an
action is taking place, and not intended to
indicate an electrical problem or that the
battery requires replacement.
After battery replacement, or in some
cases after charging the battery with an
external charger, the battery management
system requires eight hours of vehicle sleep
time to relearn the battery state of charge.
During this time your vehicle must remain
fully locked with the ignition switched off.
Note: Prior to relearning the battery state
of charge, the battery management system
may temporarily disable some electrical
systems.
Electrical Accessory Installation
To make sure the battery management
system works correctly, do not connect an
electrical device ground connection
directly to the battery negative post. This
can cause inaccurate measurements of
the battery condition and potential
incorrect system operation.
Note: If you add electrical accessories or
components to the vehicle, it may adversely
affect battery performance and durability.
This may also affect the performance of
other electrical systems in the vehicle.
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ADJUSTING THE HEADLAMPS
Vertical Aim Adjustment
The headlamps on your vehicle are
properly aimed at the assembly plant. If
your vehicle has been in an accident, the
alignment of your headlamps should be
checked by your authorized dealer.
Headlamp Aiming Target
8 feet (2.4 meters)
A
Center height of lamp to ground
B
25 feet (7.6 meters)
C
Horizontal reference line
D
Vertical Aim Adjustment Procedure
1. Park the vehicle directly in front of a wall or screen on a level surface,
approximately 25 ft (7.6 m) away.
2. Measure the height of the headlamp bulb center from the ground and mark
an
8 ft (2.4 m) horizontal reference line
on the vertical wall or screen at this
height.
Note: To see a clearer light pattern for
adjusting, you may want to block the light
from one headlamp while adjusting the
other. 3. Turn on the low beam headlamps to
illuminate the wall or screen and open
the hood. 4. On the wall or screen you will observe
a flat zone of high intensity light
located at the top of the right hand
portion of the beam pattern. If the top
edge of the high intensity light zone is
not at the horizontal reference line, the
headlamp will need to be adjusted. 5. Locate the vertical adjuster on each
headlamp. Using a Phillips #2
screwdriver, turn the adjuster either
clockwise or counterclockwise in order
to adjust the vertical aim of the
headlamp.
Note: A. LED headlamp.
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B. Halogen headlamp.
6. Repeat steps 3 thru 5 to adjust the
other headlamp.
7. Close the hood and turn off the lamps.
Horizontal Aim Adjustment
Horizontal aim is not required for this
vehicle and is not adjustable.
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 441).
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.
FUEL FILTER - 6.2L/7.3L
Your vehicle is equipped with a lifetime
fuel filter that is integrated with the fuel
tank. Regular maintenance or replacement
is not needed. CHECKING THE WIPER
BLADES
Run the tip of your fingers over the edge of
the blade to check for roughness.
Clean the wiper blades with washer fluid
or water applied with a soft sponge or
cloth.
CHANGING THE WIPER
BLADES
You can manually move the wiper arms
when the ignition is off. This allows for ease
of blade replacement and cleaning under
the blades.
1. Pull the wiper blade and arm away
from the glass.
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2. Release the wiper blade lock (A) and
separate the wiper blade from the
wiper arm.
3. Install in the reverse order.
Note: Make sure that the wiper blade locks
into place. Lower the wiper arm and blade
back on the windshield. The wiper arms will
automatically return to their normal position
when you turn the ignition on.
• Replace wiper blades at least once per
year for optimum performance.
• You can improve poor wiper quality by
cleaning the wiper blades and the
windshield.
CHANGING A BULB WARNING: Switch the lamps and
the ignition off. Failure to follow this
warning could result in serious personal
injury. WARNING: Bulbs can become hot.
Let the bulb cool down before removing
it. Failure to do so could result in
personal injury.
Use the correct specification bulb. See
Bulb Specification Chart
(page 447).
Install in the reverse order unless otherwise
stated. Front Park and Direction Indicator
Lamp Bulbs
Note:
To access the right-hand side bulbs,
remove the air intake pipe. See
Changing
the Engine Air Filter (page 357).
To access the left-hand side bulbs, remove
the washer reservoir filler tube. Vehicles with
diesel engine only. 1.
Switch all of the lamps and the ignition
off.
2. Disconnect the electrical connector.
3. Turn the bulb holder counterclockwise
and remove it.
Note: You cannot separate the bulb from
the bulb holder.
Headlamp Bulbs
Note: To access the right-hand side bulbs,
remove the air intake pipe. See
Changing
the Engine Air Filter (page 357).
To access the left-hand side bulbs, remove
the washer reservoir filler tube. Vehicles with
diesel engine only.
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1.
Switch all of the lamps and the ignition
off.
2. Disconnect the electrical connector.
3. Turn the bulb holder counterclockwise
and remove it.
Note: You cannot separate the bulb from
the bulb holder.
Note: Handle a halogen headlamp bulb
carefully and keep out of children ’s reach.
Grasp the bulb only by its plastic base and
do not touch the glass. The oil from your
hand could cause the bulb to break the next
time the headlamps are operated.
Fog Lamp Bulbs (If Equipped) 1.
Switch all of the lamps and the ignition
off.
2. To access the bulb, reach behind the bumper.
3. Disconnect the electrical connector.
4. Turn the bulb holder counterclockwise
and remove it.
Note: You cannot separate the bulb from
the bulb holder.
Note: Handle a halogen bulb carefully and
keep out of children ’s reach. Grasp the bulb
only by its plastic base and do not touch the
glass. The oil from your hand could cause
the bulb to break the next time the fog
lamps are operated.
Rear Lamps, Brake Lamps, Rear
Direction Indicator and Reversing
Lamp Bulbs
Pickup Models - Vehicles without Blind
Spot Information System 1.
Switch all of the lamps and the ignition
off.
2. Open the tailgate to expose the lamp assemblies.
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3. Remove the bolts from the tail lamp
assembly and carefully pull the lamp
assembly from the tailgate pillar by
releasing the two retaining tabs.
4. Turn the bulb holder counterclockwise
and remove it.
5. Remove the bulb by pulling it straight out.
Pickup Models - Vehicles with Blind
Spot Information System 1.
Switch all of the lamps and the ignition
off.
2. Open the tailgate to expose the lamp assemblies.
3. Remove the bolts from the tail lamp assembly and carefully pull the lamp
assembly from the tailgate pillar by
releasing the two retaining tabs.
4. Remove the screws from the blind spot
information system module cover.
5. Turn the bulb holder counterclockwise
and remove it.
6. Remove the bulb by pulling it straight out. Chassis Cabs
1.
Switch all of the lamps and the ignition
off.
2. Remove the screws and the lamp lens from lamp assembly.
3. Remove the bulb by pulling it straight out.
Cargo Lamp and Central High
Mounted Brake Lamp Bulbs
1. Switch all of the lamps and the ignition
off.
2. Remove the screws and carefully pull the lamp assembly from the vehicle to
expose the bulb sockets. 3.
Turn the bulb holder counterclockwise
and remove it.
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4. Remove the bulb by pulling it straight
out.
License Plate Lamp Bulb 1.
Switch all of the lamps and the ignition
off.
2. To access the bulb, reach behind the bumper.
3. Turn the bulb holder counterclockwise
and remove it.
4. Remove the bulb by pulling it straight out.
LED Lamps (If Equipped)
LED lamps are not serviceable items. See
an authorized dealer if they fail.
The following lamps may be LED:
• Headlamps.
• Front fog lamps.
• Rear lamps.
• High stop lamp and cargo lamp.
• License plate bulb. CHANGING THE ENGINE-
MOUNTED AND DIESEL FUEL
CONDITIONER MODULE FUEL
FILTERS - 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 two fuel filters. The first
filter mounts on top of the engine on the
left-hand side. The second filter is inside
the diesel fuel conditioner module. The
module is attached to the fuel tank in
different locations depending on the
configuration of your truck. See table
below for configurations.
Note: The module is at the front of the fuel
tank or at the front of the aft-axle fuel tank
on some models.
Regular fuel filter changes are an
important part of engine maintenance;
failing to keep with the scheduled
maintenance could lead to engine
performance issues and fuel injection
system damage. See
Scheduled
Maintenance (page 565).
Use only recommended service parts
conforming to specifications. See
Motorcraft Parts
(page 443).
Note: Using fuel that has high levels of
impurities may require more frequent filter
replacements than the service interval
specifies.
Diesel Fuel Conditioner Module
Filter
Filter Location
Use the tables below to find the location
of your filter.
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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.
Removal 1. For 2017 models, disconnect the fuel
line quick connect coupling from the in
tank fuel pump. For 2018 models and
later, skip this step but insure that the
fuel filler cap is closed before draining
the filter. Failure to close the fill cap
results in the siphoning of the entire
fuel tank contents when you open the
drain screw.
2. Locate your filter.
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