2021 FORD MUSTANG service

It is very important to use prediluted
coolant approved to the correct
specification in order to avoid plugging the
small passageways in the engine cooling
system. See Capacities and
Specifications (page 335). 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: If prediluted coolant is not available,
use the approved concentrated coolant
diluting it to 50/50 with distilled water. See
Capacities and Specifications (page 335).
Using water that has not been deionised
may contribute to deposit formation,
corrosion and plugging of the small cooling
system passageways.
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, 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 approved to the correct specification. See
Capacities and Specifications (page
335
).
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. If necessary, add enough
prediluted engine coolant to bring the
coolant level to the correct level.
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 engine coolant
in order to reach a vehicle service location.
In this instance, qualified personnel:
1. Must drain the cooling system.
2. Chemically clean the coolant system.
3. Refill with engine coolant as soon as possible.
Water alone, without engine 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.
Note: Dispose of used coolant in the
appropriate manner.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Maintenance

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.
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 for a short period of time 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 stop your vehicle. You can
continue to drive.
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:
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Maintenance

6. Tighten the filler plug until you feel a
strong resistance.
Only use fluid that meets Ford
specifications. See Capacities and
Specifications (page 335).
AUTOMATIC TRANSMISSION
FLUID CHECK
If required, have an authorized dealer check
and change the transmission fluid at the
correct service interval. See
Scheduled
Maintenance (page 441).
The automatic transmission does not have
a transmission fluid dipstick.
Refer to your scheduled maintenance
information for scheduled intervals for fluid
checks and changes. Your transmission
does not consume fluid. However, if the
transmission slips, shifts slowly or if you
notice a sign of leaking fluid, contact an
authorized dealer.
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.
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:
The brake system
could be affected if the brake fluid level
is below the MIN mark or above the MAX
mark on the brake fluid reservoir. 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.
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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 335).
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.
CLUTCH FLUID CHECK -
MANUAL TRANSMISSION
The clutch and brake systems share the
same fluid reservoir. See
Brake Fluid
Check (page 269).
POWER STEERING FLUID
CHECK
Your vehicle is equipped with an electric
power steering (EPS) system. There is no
fluid reservoir to check or fill. 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
.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Maintenance

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. WARNING:
For vehicles with
Auto-Start-Stop the battery requirement
is different. You must replace the battery
with one of exactly the same
specification.
The battery is in the engine compartment.
See
Under Hood Overview (page 258).
Your vehicle has a maintenance-free
battery. It does not require additional
water during service.
If the vehicle battery has a cover and vent
hose, make sure you correctly install it after
cleaning or replacing the battery.
For longer, trouble-free operation, keep the
top of the battery clean and dry and the
battery cables tightly fastened to the
battery terminals. If any corrosion is
present 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.
We recommend that you disconnect the
negative battery cable terminal from the
battery if you plan to store your vehicle for
an extended period.
Note: If you only disconnect the negative
battery cable terminal, make sure it is
isolated or placed away from the battery
terminal to avoid unintended connection or
arcing. If you replace the battery make sure it
matches the electrical requirements of
your vehicle.
If you disconnect or replace the battery
and your vehicle has an automatic
transmission, it must relearn its adaptive
strategy. Because of this, the transmission
may shift firmly when first driven. This is
normal operation while the transmission
fully updates its operation to optimum
shift feel.
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.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Maintenance

Poor wiper quality can be improved by
cleaning the wiper blades and the
windshield. See Cleaning the Windows
and Wiper Blades (page 294).
CHANGING A BULB
Replacing Reverse Lamp Bulbs
1. Make sure the lighting control is in the off position.
2. Locate the reverse lamp bulb under the
rear bumper of your vehicle. To access
the bulb, reach behind the bumper.
3. Disconnect the electrical sensor from the bulb by pulling it straight off. 4. Rotate the bulb counterclockwise and
remove it from the reverse lamp
assembly.
LED Lamps
LED lamps are not serviceable items.
Contact an authorized dealer if they fail.
The following are LED lamps:
• Headlamps.
• Rear lamp.
• Brake lamp.
• Front fog lamp.
• Front sidemarker
• Daytime running lamp. •
Central high mounted brake lamp.
• Front direction indicator.
• Rear direction indicator lamp.
• License plate lamp.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing MaintenanceE177487

Start Option
Allows you to select the type of countdown
the information display shows before
starting an event.
Status Screen
Provides the status of your chosen
performance-related settings.
View/Clear Results
Allows you to view and clear the last and
saved results of the Acceleration Timer,
Brake Performance, and All Time Best
results.
Track Use Maintenance Intervals
Follow these maintenance intervals for
when you use your vehicle on a track or in
a high speed event. Vehicle Use and Example
Interval
Change the engine oil and filter
One track weekend or approximately 4
hours of track use
Change the rear axle fluid
Every 500 mi (800 km) 1
1 Change the fluid every 500 mi (800 km) or when a message appears in the information
display stating that the axle fluid is over temperature.
Timing Chain
If you use your vehicle extensively at a race
track or at high rpm, it is possible to exceed
the service life of the engine timing chain.
A wrench indicator light illuminates when
it is time for you to replace your chain.
Have your vehicle checked as soon as
possible.
Adjustable Camber Front Strut
Top Mounts
(If Equipped)
Your vehicle has adjustable strut mounts
which you can use to adjust the camber of
your vehicle before and after a track event
to the specifications listed in the Road
Course Alignment Recommendations table
previously shown.
Note: After your track day is complete,
return your car to the street alignment and
tire pressures. Aerodynamics
(If Equipped)
Adjustable Rear Wing
The rear wing generates aerodynamic
down-force at speeds greater than 50 mph
(80 km/h)
.
Regularly inspect the rear wing panel and
attachment points for damage or
looseness.
You can adjust the wing using the hole
pattern at the top of the stanchion.
Moving the wing up increases rear down
force and overall understeer. Moving the
wing down decreases the rear down force
and overall understeer.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Track Use

GENERAL INFORMATION
The recommended tire inflation pressures
are on the tire information label on the
driver side B-pillar.
Check and set the tire pressure at the
ambient temperature in which you are
intending to drive your vehicle and when
the tires are cold.
Note:
Check your tire pressures regularly to
optimize fuel economy.
Only use approved wheel and tire sizes.
Using other sizes could damage your
vehicle and could make the National Type
Approval invalid.
Installation of any tires that are not the
original equipment tire size can cause the
speedometer to display incorrect vehicle
speed.
TIRE SEALANT AND INFLATOR
KIT
Note: The temporary mobility kit contains
enough sealant compound in the canister
for one tire repair only. See your authorized
dealer for replacement sealant canisters.
The kit is under the load floor in the cargo
area. The kit consists of an air compressor
to re-inflate the tire and a canister of
sealing compound that effectively seals
most punctures caused by nails or similar
objects. This kit provides a temporary tire
repair, allowing you to drive your vehicle
up to 120 mi (200 km) at a maximum
speed of 50 mph (80 km/h) to reach a tire
service location. Air compressor (inside).
A
Selector switch.
B
On and off button.
C
Air pressure gauge.
D
Sealant bottle and canister.
E
Dual purpose hose: air and
repair.
F
Tire valve connector.
G
Accessory power plug.
H
Casing/housing.
I
Bike/raft/sports ball adapters.
J
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Wheels and TiresE175977