2021 JEEP WRANGLER service

* The actual interval for changing engine oil
and replacing the engine oil filter depends on
the vehicle usage conditions and is signalled
by the warning light or message in the instru-
ment panel. In all cases, never exceed 1 year/
15,000 miles (24,000 km).
** DOT 4 brake fluid is time based only;
mileage intervals do not apply.
WARNING!
• You can be badly injured working on or
around a motor vehicle. Do only service
work for which you have the knowledge
and the right equipment. If you have any
doubt about your ability to perform a
service job, take your vehicle to a com-
petent mechanic.
• Failure to properly inspect and maintain
your vehicle could result in a component
malfunction and effect vehicle handling
and performance. This could cause an
accident.
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by gently spraying water from a garden hose
vertically down the face of the A/C condenser
(if equipped) or the back of the radiator core.
Check the engine cooling system hoses for
brittle rubber, cracking, tears, cuts, and
tightness of the connection at the coolant
recovery bottle and radiator. Inspect the en-
tire system for leaks. DO NOT REMOVE THE
COOLANT PRESSURE CAP WHEN THE
COOLING SYSTEM IS HOT.
Adding Washer Fluid
The fluid reservoir for the windshield washers
and the rear window washer (if equipped) is
shared. The fluid reservoir is located in the
engine compartment. Be sure to check the
fluid level at regular intervals. Fill the reservoir
with windshield washer solvent only (not radia-
tor antifreeze). When refilling the washer fluid
reservoir, take some washer fluid and apply it to
a cloth or towel and wipe clean the wiper
blades; this will help blade performance.
To prevent freeze-up of your windshield
washer system in cold weather, select a solu-
tion or mixture that meets or exceeds the
temperature range of your climate. This rat-
ing information can be found on most washer
fluid containers.
WARNING!
Commercial windshield washer solvents
are flammable. They could ignite and burn
you. Care must be exercised when filling or
working around the washer solution.
Brake System
In order to assure brake system performance,
all brake system components should be in-
spected periodically. Refer to the “Mainte-
nance Plan” in this section for the proper
maintenance intervals.
WARNING!
Riding the brakes can lead to brake failure
and possibly a collision. Driving with your
foot resting or riding on the brake pedal
WARNING!
can result in abnormally high brake tem-
peratures, excessive lining wear, and pos-
sible brake damage. You would not have
your full braking capacity in an emergency.
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 cylin-
der 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 sys-
tem for leaks.
Refer to “Fluids And Lubricants” in “Techni-
cal Specifications” for further information.
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5. Place the gear selector momentarily into
each gear position (allowing time for the
transmission to fully engage in each posi-
tion), ending with the transmission in
PARK.
6. Remove the dipstick, wipe it clean and
reinsert it until seated.
7. Remove the dipstick again and note the
fluid level on both sides. The fluid level
reading is only valid if there is a solid
coating of oil on both sides of the dipstick.
Note that the holes in the dipstick will be
full of fluid if the actual level is at or above
the hole. The fluid level should be be-
tween the HOT (upper) reference holes on
the dipstick at normal operating tempera-
ture. If the fluid level is low, add fluid
through the dipstick tube to bring it to the
proper level.Do not overfill.Use ONLY the
specified fluid (refer to "Fluids And Lubri-
cants" under “Technical Specifications”
for fluid specifications). After adding any
quantity of oil through the dipstick tube,
wait a minimum of two minutes for the oil
to fully drain into the transmission before
rechecking the fluid level.NOTE:
• The holes in the dipstick will be full of
fluid if the actual level is at or above the
hole.
• If it is necessary to check the transmis-
sion below the operating temperature,
the fluid level should be between the
two COLD (lower) holes on the dipstick
with the fluid at approximately 80°F
(27°C). If the fluid level is correctly
established at 80° F (27°C), it should
be between the HOT (upper) reference
holes when the transmission reaches
180° F (82°C). Remember it is best to
check the level at the normal operating
temperature.
CAUTION!
If the fluid temperature is below 50°F
(10°C) it may not register on the dipstick.
Do not add fluid until the temperature is
elevated enough to produce an accurate
reading. Run the engine at idle, in PARK,
to warm the fluid.8. Reinstall the engine cover and snap it
down securely onto the four mounting
studs.
9. Check for leaks. Release the parking
brake.
NOTE:
To prevent dirt and water from entering the
transmission after checking or replenishing
fluid, make sure that the dipstick cap is
properly reseated. It is normal for the dipstick
cap to spring back slightly from its fully
seated position, as long as its seal remains
engaged in the dipstick tube.
Fluid Level Check — 2.8L Turbo Diesel
Engine
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 trans-
mission filler tube is capped and no dipstick
is provided. An authorized dealer can check
your transmission fluid level using a special
service dipstick.
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If you notice fluid leakage or transmission
malfunction, visit an authorized dealer im-
mediately to have the transmission fluid level
checked. Operating the vehicle with an im-
proper fluid level can cause severe transmis-
sion damage.
Maintenance-Free Battery
Your vehicle is equipped with a maintenance-
free battery. You will never have to add water,
nor is periodic maintenance required.
WARNING!
• Battery fluid is a corrosive acid solution
and can burn or even blind you. Do not
allow battery fluid to contact your eyes,
skin, or clothing. Do not lean over a
battery when attaching clamps. If acid
splashes in eyes or on skin, flush the
area immediately with large amounts of
water. Refer to “Jump Starting Proce-
dure” in “In Case Of Emergency” for
further information.
• Battery gas is flammable and explosive.
Keep flame or sparks away from the
battery. Do not use a booster battery or
WARNING!
any other booster source with an output
greater than 12 Volts. Do not allow cable
clamps to touch each other.
• Battery posts, terminals, and related ac-
cessories contain lead and lead com-
pounds. Wash hands after handling.
CAUTION!
• It is essential when replacing the cables
on the battery that the positive cable is
attached to the positive post and the
negative cable is attached to the nega-
tive post. Battery posts are marked posi-
tive (+) and negative (-) and are identi-
fied on the battery case. Cable clamps
should be tight on the terminal posts
and free of corrosion.
• If a “fast charger” is used while the
battery is in the vehicle, disconnect both
vehicle battery cables before connecting
the charger to the battery. Do not use
a “fast charger” to provide starting volt-
age.
Air Conditioner Maintenance
For best possible performance, your air con-
ditioner should be checked and serviced by
an authorized dealer at the start of each warm
season. This service should include cleaning
of the condenser fins and a performance test.
Drive belt tension should also be checked at
this time.
WARNING!
• Use only refrigerants and compressor
lubricants approved by the manufac-
turer for your air conditioning system.
Some unapproved refrigerants are flam-
mable and can explode, injuring you.
Other unapproved refrigerants or lubri-
cants can cause the system to fail, re-
quiring costly repairs. Refer to Warranty
Information Book, located in your own-
er’s information kit, for further warranty
information.
• The air conditioning system contains re-
frigerant under high pressure. To avoid
risk of personal injury or damage to the
system, adding refrigerant or any repair
SERVICING AND MAINTENANCE
186

WARNING!
requiring lines to be disconnected
should be done by an experienced tech-
nician.
CAUTION!
Do not use chemical flushes in your air
conditioning system as the chemicals can
damage your air conditioning components.
Such damage is not covered by the New
Vehicle Limited Warranty.
Refrigerant Recovery And Recycling R-134a
— If Equipped
R-134a Air Conditioning Refrigerant is a
hydrofluorocarbon (HFC) that is an ozone-
friendly substance. The manufacturer recom-
mends that air conditioning service be per-
formed by an authorized dealer or other
service facilities using recovery and recycling
equipment.NOTE:
Use only manufacturer approved A/C system
PAG compressor oil and refrigerants.
Refrigerant Recovery And Recycling —
R–1234yf
R–1234yf Air Conditioning Refrigerant is a
hydrofluoroolefin (HFO) that is endorsed by
the Environmental Protection Agency and is
an ozone-friendly substance with a low
global-warming potential. The manufacturer
recommends that air conditioning service be
performed by an authorized dealer using re-
covery and recycling equipment.
NOTE:
Use only manufacturer approved A/C system
PAG compressor oil, and refrigerants.
Air Conditioning Filter Replacement (A/C Air
Filter)
WARNING!
Do not remove the cabin air filter while the
vehicle is running, or while the ignition is
in the ACC or ON/RUN mode. With the
cabin air filter removed and the blower
operating, the blower can contact hands
and may propel dirt and debris into your
eyes, resulting in personal injury.
The A/C air filter is located in the fresh air
inlet behind the glove compartment. Perform
the following procedure to replace the filter:
1. Open the glove compartment and remove
all contents.
2. Push in on the sides of the glove compart-
ment and lower the door.
187

CAUTION!
The cabin air filter is identified with an
arrow to indicate airflow direction through
the filter. Failure to properly install the
filter will result in the need to replace it
more often.
8. Close A/C Air Filter access doors and se-
cure retaining tabs.
9. Rotate the glove compartment door back
into position.
Refer to the “Maintenance Plan” for the
proper maintenance intervals.
DEALER SERVICE
An authorized dealer has the qualified service
personnel, special tools, and equipment to
perform all service operations in an expert
manner. Service Manuals are available which
include detailed service information for your
vehicle. Refer to these Service Manuals be-
fore attempting any procedure yourself.NOTE:
Intentional tampering with emissions control
systems may void your warranty and could
result in civil penalties being assessed
against you.
WARNING!
You can be badly injured working on or
around a motor vehicle. Only do service
work for which you have the knowledge
and the proper equipment. If you have any
doubt about your ability to perform a ser-
vice job, take your vehicle to a competent
mechanic.
Windshield Wiper Blades
Clean the rubber edges of the wiper blades
and the windshield periodically with a sponge
or soft cloth and a mild nonabrasive cleaner.
This will remove accumulations of salt or road
film.Operation of the wipers on dry glass for long
periods may cause deterioration of the wiper
blades. Always use washer fluid when using
the wipers to remove salt or dirt from a dry
windshield.
Avoid using the wiper blades to remove frost
or ice from the windshield. Keep the blade
rubber out of contact with petroleum prod-
ucts such as engine oil, gasoline, etc.
NOTE:
Life expectancy of wiper blades varies de-
pending on geographical area and frequency
of use. Poor performance of blades may be
present with chattering, marks, water lines or
wet spots. If any of these conditions are
present, clean the wiper blades or replace as
necessary.
The wiper blades and wiper arms should be
inspected periodically, not just when wiper
performance problems are experienced. This
inspection should include the following
points:
• Wear Or Uneven Edges
• Foreign Material
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past its stop far enough to unsnap the
wiper blade pivot pin from the receptacle
on the end of the wiper arm.
NOTE:
Resistance will be accompanied by an
audible snap.3. Still grasping the wiper blade, move the
wiper blade away from the wiper arm to
disengage.Installing The Rear Wiper
1. Insert the wiper blade pivot pin into the
opening on the end of the wiper arm. Grab
the bottom end of the wiper arm with one
hand, and apply pressure to the wiper
blade flush with the wiper arm until it
snaps into place.
2. Lower the wiper blade onto the glass and
snap the wiper arm pivot cap back into
place.
RAISING THE VEHICLE
In the case where it is necessary to raise the
vehicle, go to an authorized dealer or service
station.
Wiper Blade Removed From Wiper Arm
1 — Wiper Arm
2 — Wiper Blade
Wiper Blade Removed From Wiper Arm
1 — Wiper Arm
2 — Wiper Blade
SERVICING AND MAINTENANCE
192

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 repair-
able).
• The puncture is no greater thana¼ofan
inch (6 mm).
Consult an authorized tire dealer for tire re-
pairs 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).
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 therun flat mode it has limited driving capabili-
ties and needs to be replaced immediately. A
Run Flat tire is not repairable.
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 section for
more information.
Tire Spinning
When stuck in mud, sand, snow, or ice con-
ditions, do not spin your vehicle's wheels
above 30 mph (48 km/h) or for longer than
30 seconds continuously without stopping.
Refer to “Freeing A Stuck Vehicle” in “In
Case Of Emergency” for further information.
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 sec-
WARNING!
onds continuously when you are stuck, and
do not let anyone near a spinning wheel,
no matter what the speed.
Tread Wear Indicators
Tread wear indicators are in the original
equipment tires to help you in determining
when your tires should be replaced.
These indicators are molded into the bottom
of the tread grooves. They will appear as
bands when the tread depth becomes a
1/16 of an inch (1.6 mm). When the tread is
Tire Tread
1 — Worn Tire
2 — New Tire
195