2023 JEEP WRANGLER warning

330SERVICING AND MAINTENANCE
NOTE:
It is the owner's responsibility to maintain the proper
level of protection against freezing according to the
temperatures occurring in the area where the vehicle is
operated.
 Use care when filling under hood fluids such as engine
oil, washer fluid, antifreeze, etc., to minimize spillage
onto the top of the engine. Any excess fluid that is
spilled onto the top of the engine should be removed
using compressed air or an absorbent cloth.
 Some vehicles require special tools to add coolant
properly. Failure to fill these systems properly could
lead to severe internal engine damage. If any coolant is
needed to be added to the system, please contact an
authorized dealer.
 Mixing engine coolant types is not recommended and
can result in cooling system damage. If HOAT and OAT
coolant are mixed in an emergency, have an authorized
dealer drain, flush, and refill with OAT coolant
(conforming to MS.90032) as soon as possible.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of engine
coolant (antifreeze), and to ensure that engine coolant will
return to the radiator from the coolant expansion bottle/
recovery tank if so equipped.
The cap should be inspected and cleaned if there is any
accumulation of foreign material on the sealing surfaces.
Disposal Of Used Coolant
Used ethylene glycol-based coolant (antifreeze) OAT or
HOAT, is a regulated substance requiring proper disposal.
Check with your local authorities to determine the disposal
rules for your community. To prevent ingestion by animals
or children, do not store ethylene glycol-based coolant in
open containers or allow it to remain in puddles on the
ground, clean up any ground spills immediately. If
ingested, seek emergency assistance immediately.
Coolant Level
The coolant bottle provides a quick visual method for
determining that the coolant level is adequate. With the
engine OFF and cold, the level of the engine coolant
(antifreeze) in the bottle should be between the ranges
indicated on the bottle. The radiator normally remains completely full, so there is
no need to remove the radiator/coolant pressure cap
unless checking for engine coolant freeze point or
replacing coolant. Advise your service attendant of this. As
long as the engine operating temperature is satisfactory,
the coolant bottle need only be checked once a month.
When additional engine coolant is needed to maintain the
proper level, only OAT coolant that meets the
requirements of the manufacturer Material Standard
MS.90032 should be added to the coolant bottle. Do not
overfill.
Engine Coolant Level — 2.0L
WARNING!

Do not open hot engine cooling system. Never add
engine coolant (antifreeze) when the engine is over -
heated. Do not loosen or remove the cap to cool an
overheated engine. Heat causes pressure to build up
in the cooling system. To prevent scalding or injury,
do not remove the pressure cap while the system is
hot or under pressure.
 Do not use a pressure cap other than the one speci -
fied for your vehicle. Personal injury or engine
damage may result.
WARNING!
 Do not open hot engine cooling system. Never add
engine coolant (antifreeze) when the engine is over -
heated. Do not loosen or remove the cap to cool an
overheated engine. Heat causes pressure to build up
in the cooling system. To prevent scalding or injury,
do not remove the pressure cap while the system is
hot or under pressure.
 Do not use a pressure cap other than the one speci -
fied for your vehicle. Personal injury or engine
damage may result.

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SERVICING AND MAINTENANCE331
(Continued)
With the engine OFF and cold, the level of the engine
coolant should be within the OK range between the ADD
and FULL range on the dipstick.

1. Remove the cap with level dipstick from the engine
coolant bottle.

2. Clean off the coolant from the dipstick.
3. Rest the cap on the opening of the coolant bottle without tightening the cap.
4. Remove the cap with dipstick and check the coolant level on the dipstick.
The radiator normally remains completely full, so there is
no need to remove the radiator/coolant pressure cap
unless checking for engine coolant freeze point or
replacing coolant. Advise your service attendant of this. As
long as the engine operating temperature is satisfactory,
the coolant bottle need only be checked once a month.
When additional engine coolant is needed to maintain the
proper level, only OAT coolant that meets the
requirements of the manufacturer Material Standard
MS.90032 should be added to the coolant bottle. Do not
overfill.
Cooling System Notes
NOTE:When the vehicle is stopped after a few miles/kilometers
of operation, you may observe vapor coming from the front
of the engine compartment. This is normally a result of
moisture from rain, snow, or high humidity accumulating
on the radiator and being vaporized when the thermostat
opens, allowing hot engine coolant (antifreeze) to enter
the radiator. If an examination of your engine compartment shows no
evidence of radiator or hose leaks, the vehicle may be
safely driven. The vapor will soon dissipate.

Do not overfill the coolant expansion bottle.
 Check the coolant freeze point in the radiator and in
the coolant expansion bottle. If engine coolant needs
to be added, the contents of the coolant expansion
bottle must also be protected against freezing.
 If frequent engine coolant additions are required, the
cooling system should be pressure tested for leaks.
 Maintain engine coolant concentration at a minimum
of 50% OAT coolant (conforming to MS.90032) and
distilled water for proper corrosion protection of your
engine which contains aluminum components.
 Make sure that the coolant expansion bottle overflow
hoses are not kinked or obstructed.
 Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean.
 Do not change the thermostat for Summer or Winter
operation. If replacement is ever necessary, install
ONLY the correct type thermostat. Other designs may
result in unsatisfactory engine cooling performance,
poor gas mileage, and increased emissions.BRAKE SYSTEM
In order to ensure brake system performance, all brake
system components should be inspected periodically. For
the proper maintenance intervals
Úpage 307.
Fluid Level Check — Brake Master Cylinder
The fluid level of the master cylinder should be checked
whenever the vehicle is serviced, or immediately if the
Brake System Warning Light is on. If necessary, add fluid
to bring level within the designated marks on the side of
the reservoir of the brake master cylinder. Be sure to clean
the top of the master cylinder area before removing cap.
With disc brakes, fluid level can be expected to fall as the
brake pads wear. Brake fluid level should be checked
when pads are replaced. If the brake fluid is abnormally
low, check the system for leaks
Úpage 376.
WARNING!
Riding the brakes can lead to brake failure and possibly
a collision. Driving with your foot resting or riding on the
brake pedal can result in abnormally high brake
temperatures, excessive lining wear, and possible brake
damage. You would not have your full braking capacity
in an emergency.
WARNING!
Use only the manufacturer recommended brake fluid Úpage 376. Using the wrong type of brake fluid can
severely damage your brake system and/or impair its
performance. The proper type of brake fluid for your
vehicle is also identified on the original factory
installed hydraulic master cylinder reservoir.
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332SERVICING AND MAINTENANCE
FRONT/REAR AXLE FLUID
For normal service, periodic fluid level checks are not
required. When the vehicle is serviced for other reasons
the exterior surfaces of the axle assembly should be
inspected. If gear oil leakage is suspected inspect the fluid
level.
Fluid Level Check
Lubricant should be approximately 1/8 inch (3 mm) below
the bottom edge of the oil fill hole.
NOTE:Make sure that the vehicle is level and supported by the
axles.
Adding Fluid
Add lubricant only at the fill hole and only to the level
specified above.
Selection Of Lubricant
Use only manufacturer recommended fluid Úpage 376.
TRANSFER CASE
Fluid Level Check
The fluid level should be to the bottom edge of the fill hole
when the vehicle is in a level position.

Transfer Case

Drain And Refill
For the proper maintenance intervals Úpage 307.
Selection Of Lubricant
Use only the manufacturer recommended fluid Úpage 376.
MANUAL TRANSMISSION — IF EQUIPPED
Fluid Level Check
Check the fluid level by removing the fill plug. The fluid
level should be between the bottom of the fill hole and a
point not more than 3/16 of an inch (4.76 mm) below the
bottom of the hole.
Add fluid, if necessary, to maintain the proper level.
Frequency Of Fluid Change
Under normal operating conditions, the fluid installed at
the factory will give satisfactory lubrication for the life of
the vehicle. If the fluid becomes contaminated with water,
it should be changed immediately. Otherwise, change the
fluid as recommended in the Maintenance Plan. Refer to
the Maintenance Plan for the proper maintenance
intervals
Úpage 307.
Selection Of Lubricant
Use only the manufacturer recommended manual
transmission fluid Úpage 376.

To avoid contamination from foreign matter or mois -
ture, use only new brake fluid or fluid that has been
in a tightly closed container. Keep the master
cylinder reservoir cap secured at all times. Brake
fluid in an open container absorbs moisture from the
air resulting in a lower boiling point. This may cause
it to boil unexpectedly during hard or prolonged
braking, resulting in sudden brake failure. This could
result in a collision.
 Overfilling the brake fluid reservoir can result in
spilling brake fluid on hot engine parts, causing the
brake fluid to catch fire. Brake fluid can also damage
painted and vinyl surfaces, care should be taken to
avoid its contact with these surfaces.
 Do not allow petroleum-based fluid to contaminate
the brake fluid. Brake seal components could be
damaged, causing partial or complete brake failure.
This could result in a collision.
WARNING!
1 — Fill hole
2 — Drain hole

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SERVICING AND MAINTENANCE333
(Continued)
AUTOMATIC TRANSMISSION —
I
F EQUIPPED
Special Additives
It is strongly recommended against using any special
additives in the transmission. Automatic Transmission
Fluid (ATF) is an engineered product and its performance
may be impaired by supplemental additives. Therefore, do
not add any fluid additives to the transmission. Avoid
using transmission sealers as they may adversely affect
seals.
Fluid Level Check
The fluid level is preset at the factory and does not require
adjustment under normal operating conditions. Routine
fluid level checks are not required; therefore the
transmission has no dipstick. An authorized dealer can
check your transmission fluid level using special service
tools. If you notice fluid leakage or transmission
malfunction, visit an authorized dealer immediately to
have the transmission fluid level checked. Operating the
vehicle with an improper fluid level can cause severe
transmission damage.
Fluid And Filter Changes
Under normal operating conditions, the fluid installed at
the factory will provide satisfactory lubrication for the life
of the vehicle.
Routine fluid and filter changes are not required. However,
change the fluid and filter if the fluid becomes
contaminated (with water, etc.), or if the transmission is
disassembled for any reason.
Selection Of Lubricant
It is important to use the proper transmission fluid to
ensure optimum transmission performance and life. Use
only the manufacturer specified transmission fluid
Úpage 376. It is important to maintain the transmission
fluid at the correct level using the recommended fluid.
NOTE:No chemical flushes should be used in any transmission;
only the approved lubricant should be used.
FUSES
General Information
CAUTION!
Do not use chemical flushes in your transmission as the
chemicals can damage your transmission components.
Such damage is not covered by the New Vehicle Limited
Warranty.
CAUTION!
If a transmission fluid leak occurs, visit an authorized
dealer immediately. Severe transmission damage may
occur. An authorized dealer has the proper tools to
adjust the fluid level accurately.
CAUTION!
Using a transmission fluid other than the manufacturer
recommended fluid may cause deterioration in
transmission shift quality and/or torque converter
shudder
Úpage 376.
WARNING!
 When replacing a blown fuse, always use an appro -
priate replacement fuse with the same amp rating as
the original fuse. Never replace a fuse with another
fuse of higher amp rating. The use of a fuse with a
rating other than indicated may result in a dangerous
electrical system overload. If a properly rated fuse
continues to blow, it indicates a problem in the circuit
that must be corrected. Never replace a blown fuse
with metal wires or any other material. Failure to use
proper fuses may result in serious personal injury,
fire and/or property damage.
 Before replacing a fuse, make sure that the ignition
is off and that all the other services are switched off
and/or disengaged.
 If the replaced fuse blows again, contact an autho -
rized dealer.
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334SERVICING AND MAINTENANCE
The fuses protect electrical systems against excessive
current.
When a device does not work, you must check the fuse
element inside the blade fuse for a break/melt.
Also, please be aware that using power outlets for
extended periods of time with the engine off may result in
vehicle battery discharge.

Blade Fuses

Power Distribution Center (PDC)
The Power Distribution Center is located in the engine
compartment near the battery. This center contains
cartridge fuses, mini fuses, and relays. The PDC top cover
is labeled with each serviceable fuse/relay location,
function, and size.

If a general protection fuse for safety systems (air
bag system, braking system), power unit systems
(engine system, gearbox system) or steering system
blows, contact an authorized dealer.WARNING!
1 — Fuse Element
2 — Blade Fuse with a good/functional fuse element
3 — Blade fuse with a bad/not functional fuse element
(blown fuse)
CAUTION!
When installing the power distribution center cover, it is
important to ensure the cover is properly positioned
and fully latched. Failure to do so may allow water to get
into the power distribution center and possibly result in
an electrical system failure.

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SERVICING AND MAINTENANCE351
WARNING!
Overloading of your tires is dangerous. Overloading can cause tire failure, affect vehicle handling, and increase your stopping distance. Use tires of the recommended load capacity
for your vehicle. Never overload them.
8

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352SERVICING AND MAINTENANCE
(Continued)
TIRES — GENERAL INFORMATION
Tire Pressure
Proper tire inflation pressure is essential to the safe and
satisfactory operation of your vehicle. Four primary areas
are affected by improper tire pressure:
Safety
 Fuel Economy
 Tread Wear
 Ride Comfort and Vehicle Stability
Safety Both underinflation and overinflation affect the stability of
the vehicle and can produce a feeling of sluggish response
or over responsiveness in the steering.
NOTE:

Unequal tire pressures from side to side may cause
erratic and unpredictable steering response.
 Unequal tire pressure from side to side may cause the
vehicle to drift left or right.
Fuel Economy
Underinflated tires will increase tire rolling resistance
resulting in higher fuel consumption.
Tread Wear
Improper cold tire inflation pressures can cause abnormal
wear patterns and reduced tread life, resulting in the need
for earlier tire replacement.
Ride Comfort And Vehicle Stability
Proper tire inflation contributes to a comfortable ride.
Overinflation produces a jarring and uncomfortable ride.
Tire Inflation Pressures
The proper cold tire inflation pressure is listed on the
driver's side B-pillar or rear edge of the driver's side door. At least once a month:

Check and adjust tire pressure with a good quality
pocket-type pressure gauge. Do not make a visual
judgement when determining proper inflation. Tires
may look properly inflated even when they are
under-inflated.
 Inspect tires for signs of tire wear or visible damage.
Inflation pressures specified on the placard are always
“cold tire inflation pressure”. Cold tire inflation pressure is
defined as the tire pressure after the vehicle has not been
driven for at least three hours, or driven less than 1 mile
(1.6 km) after sitting for a minimum of three hours. The
cold tire inflation pressure must not exceed the maximum
inflation pressure molded into the tire sidewall.
Check tire pressures more often if subject to a wide range
of outdoor temperatures, as tire pressures vary with
temperature changes.
Tire pressures change by approximately 1 psi (7 kPa) per
12°F (7°C) of air temperature change. Keep this in mind
when checking tire pressure inside a garage, especially in
the Winter.
WARNING!
 Improperly inflated tires are dangerous and can
cause collisions.
 Underinflation increases tire flexing and can result in
overheating and tire failure.
 Overinflation reduces a tire's ability to cushion shock.
Objects on the road and chuckholes can cause
damage that result in tire failure.
 Overinflated or underinflated tires can affect vehicle
handling and can fail suddenly, resulting in loss of
vehicle control.
 Unequal tire pressures can cause steering problems.
You could lose control of your vehicle.
 Unequal tire pressures from one side of the vehicle
to the other can cause the vehicle to drift to the right
or left.
Always drive with each tire inflated to the recom -
mended cold tire inflation pressure.
WARNING!
CAUTION!
After inspecting or adjusting the tire pressure, always
reinstall the valve stem cap. This will prevent moisture
and dirt from entering the valve stem, which could
damage the valve stem.

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SERVICING AND MAINTENANCE353
Example: If garage temperature = 68°F (20°C) and the
outside temperature = 32°F (0°C) then the cold tire
inflation pressure should be increased by 3 psi (21 kPa),
which equals 1 psi (7 kPa) for every 12°F (7°C) for this
outside temperature condition.
Tire pressure may increase from 2 to 6 psi (13 to 40 kPa)
during operation. DO NOT reduce this normal pressure
build up or your tire pressure will be too low.
Tire Pressures For High Speed Operation
The manufacturer advocates driving at safe speeds and
within posted speed limits. Where speed limits or
conditions are such that the vehicle can be driven at high
speeds, maintaining correct tire inflation pressure is very
important. Increased tire pressure and reduced vehicle
loading may be required for high-speed vehicle operation.
Refer to an authorized tire dealer or original equipment
vehicle dealer for recommended safe operating speeds,
loading and cold tire inflation pressures.
Radial Ply Tires
Tire Repair
If your tire becomes damaged, it may be repaired if it
meets the following criteria:
The tire has not been driven on when flat.
 The damage is only on the tread section of your tire
(sidewall damage is not repairable).
 The puncture is no greater than ¼ of an inch (6 mm).
Consult an authorized tire dealer for tire repairs and
additional information.
Damaged Run Flat tires, or Run Flat tires that have
experienced a loss of pressure should be replaced
immediately with another Run Flat tire of identical size and
service description (Load Index and Speed Symbol).
Replace the tire pressure sensor as well as it is not
designed to be reused.
Run Flat Tires — If Equipped
Run Flat tires allow you the capability to drive 50 miles
(80 km) at 50 mph (80 km/h) after a rapid loss of inflation
pressure. This rapid loss of inflation is referred to as the
Run Flat mode. A Run Flat mode occurs when the tire
inflation pressure is of/or below 14 psi (96 kPa). Once a
Run Flat tire reaches the run flat mode it has limited driving capabilities and needs to be replaced immediately.
A Run Flat tire is not repairable. When a Run Flat tire is
changed after being driven in a Run Flat mode 14 psi
(96 kPa) condition, please replace the TPMS sensor as it
is not designed to be reused.
NOTE:TPMS sensor must be replaced after driving the vehicle on
a flat tire condition.
It is not recommended driving a vehicle loaded at full
capacity or to tow a trailer while a tire is in the Run Flat
mode.
See the Tire Pressure Monitoring System section for more
information.
Tire Spinning
When stuck in mud, sand, snow, or ice conditions, do not
spin your vehicle's wheels above 30 mph (48 km/h) or for
longer than 30 seconds continuously without stopping.
For further information
Úpage 302.WARNING!
High speed driving with your vehicle under maximum
load is dangerous. The added strain on your tires could
cause them to fail. You could have a serious collision.
Do not drive a vehicle loaded to the maximum capacity
at continuous speeds above 75 mph (120 km/h).
WARNING!
Combining radial ply tires with other types of tires on
your vehicle will cause your vehicle to handle poorly.
The instability could cause a collision. Always use radial
ply tires in sets of four. Never combine them with other
types of tires.
WARNING!
Fast spinning tires can be dangerous. Forces generated
by excessive wheel speeds may cause tire damage or
failure. A tire could explode and injure someone. Do not
spin your vehicle's wheels faster than 30 mph
(48 km/h) for more than 30 seconds continuously
when you are stuck, and do not let anyone near a spin
-
ning wheel, no matter what the speed.8

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