2023 JEEP WRANGLER warning

SERVICING AND MAINTENANCE317
CHECKING OIL LEVEL
To ensure proper engine lubrication, the engine oil must
be maintained at the correct level. Check the oil level at
regular intervals, such as every fuel stop. The best time to
check the engine oil level is about five minutes after a fully
warmed up engine is shut off.
Checking the oil while the vehicle is on level ground will
improve the accuracy of the oil level readings.
There are four possible dipstick types:
Crosshatched zone.
 Crosshatched zone marked SAFE.
 Crosshatched zone marked with MIN at the low end of
the range and MAX at the high end of the range.
 Crosshatched zone marked with dimples at the MIN
and the MAX ends of the range.
NOTE:Always maintain the oil level within the crosshatch
markings on the dipstick.
NOTE: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.
Adding 1 qt (1 L) of oil when the reading is at the low end
of the dipstick range will raise the oil level to the high end
of the range marking.
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 radiator 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 solution or mixture that meets or
exceeds the temperature range of your climate. This rating
information can be found on most washer fluid containers.
NOTE: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.
MAINTENANCE-FREE BATTERY
Your vehicle is equipped with a maintenance-free battery.
You will never have to add water, and periodic
maintenance is not required.
CAUTION!
Overfilling or underfilling the crankcase will cause
aeration or loss of oil pressure. This could damage your
engine.
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.
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
Úpage 298.
 Battery gas is flammable and explosive. Keep flame
or sparks away from the battery. Do not use a
booster battery or 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 accessories
contain lead and lead compounds. Wash hands after
handling.
 Vehicles with the Stop/Start system will be equipped
with two batteries. Both the main and the supple -
mental batteries must be disconnected to
completely de-energize the 12 Volt electrical system.
 Serious injury or death could result if you do not
disconnect both batteries. To learn how to properly
disconnect, see an authorized dealer.
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318SERVICING AND MAINTENANCE
PRESSURE WASHING
Cleaning the engine compartment with a high pressure
washer is not recommended.
VEHICLE MAINTENANCE
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 before
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.
ENGINE OIL
Engine Oil Selection
For engine oil selection Úpage 374.
American Petroleum Institute (API)
Approved Engine Oil
These symbols mean that the oil has been certified by the
API. The manufacturer only recommends API trademark
oils.
The API Starburst trademark certifies 0W-20,
0W-30 and 5W-30 engine oils.
The API Donut trademark certifies 0W-40 and
5W-40 engine oil.
Synthetic Engine Oils
Your engine was designed for synthetic engine oils, only
use synthetic API approved engine oils.
Synthetic engine oils which do not have both the correct
API trademark and the correct SAE viscosity grade
numbers should not be used.
CAUTION!
It is essential when replacing the cables on the
battery that the positive cable is attached to the posi -
tive post and the negative cable is attached to the
negative post. Battery posts are marked positive (+)
and negative (-) and are identified 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 voltage.
 Vehicles with the Stop/Start system will be equipped
with two batteries. Both the main and the supple -
mental batteries must be disconnected to
completely de-energize the 12 Volt electrical system.
 If the negative battery cables are not isolated prop -
erly it can cause a potential power spike or surge in
the system, resulting in damage to essential elec -
trical components.
CAUTION!
Precautions have been taken to safeguard all parts and
connections however, the pressures generated by these
machines is such that complete protection against
water ingress cannot be guaranteed.
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 service job, take
your vehicle to a competent mechanic.
CAUTION!
Do not use chemical flushes in your engine oil as the
chemicals can damage your engine. Such damage is
not covered by the New Vehicle Limited Warranty.

23_JL_OM_EN_USC_t.book Page 318

SERVICING AND MAINTENANCE319
Materials Added To Engine Oil
The manufacturer strongly recommends against the
addition of any additives (other than leak detection dyes)
to the engine oil. Engine oil is an engineered product and
its performance may be impaired by supplemental
additives.
Disposing Of Used Engine Oil And Oil
Filters
Care should be taken in disposing of used engine oil and
oil filters from your vehicle. Used oil and oil filters,
indiscriminately discarded, can present a problem to the
environment. Contact an authorized dealer, service
station or governmental agency for advice on how and
where used oil and oil filters can be safely discarded in
your area.
ENGINE OIL FILTER
The engine oil filter should be replaced with a new filter at
every engine oil change.
Engine Oil Filter Selection
A full-flow type disposable oil filter should be used for
replacement. The quality of replacement filters varies
considerably. We recommend using a Mopar® Engine Oil
Filter. If a Mopar® Engine Oil Filter is unavailable only use
filters that meet or exceed SAE/USCAR-36 Filter
Performance Requirements.
ENGINE AIR CLEANER FILTER
For the proper maintenance intervals Úpage 307 for
gasoline engines or Úpage 311 for diesel engines.
NOTE:Be sure to follow the “Severe Duty Conditions” mainte -
nance interval if applicable.
Engine Air Cleaner Filter Selection
The quality of replacement engine air cleaner filters varies
considerably. Only high quality Mopar® filters should be
used.
Engine Air Cleaner Filter Inspection and
Replacement— Gasoline Engine
Follow the recommended maintenance intervals as shown
in the Maintenance Schedule in this section.
Engine Air Cleaner Filter Removal

1. Loosen the fasteners from the engine air cleaner filter cover using a suitable tool.

Engine Air Cleaner Filter Cover

2. Lift the engine air cleaner filter cover to access the engine air cleaner filter.
WARNING!
The air induction system (air cleaner, hoses, etc.) can
provide a measure of protection in the case of engine
backfire. Do not remove the air induction system (air
cleaner, hoses, etc.) unless such removal is necessary
for repair or maintenance. Make sure that no one is
near the engine compartment before starting the
vehicle with the air induction system (air cleaner, hoses,
etc.) removed. Failure to do so can result in serious
personal injury.
1 — Fasteners
2 — Engine Air Cleaner Filter Cover8

23_JL_OM_EN_USC_t.book Page 319

SERVICING AND MAINTENANCE323
10. Lubricate o-ring on the cap with clean engine oil.
11. Install the new fuel filter cartridge onto the cap.
12. Insert the cap and filter into the housing with
clockwise rotation, use a socket to tighten.
13. Push the ignition switch twice without your foot on the brake to place vehicle in RUN position. This will
activate the in tank fuel pump for approximately 30
seconds. Repeat this process twice to prime the fuel
system. Start the engine using the Normal Starting
procedure. After engine start, verify the fuel filter cap
does not leak.
PRIMING IF THE ENGINE HAS RUN OUT
O
F FUEL — DIESEL ENGINE

1. Add a substantial amount of fuel to the tank, approx -
imately 2 to 5 gal (8L to 19L).

2. Push ignition switch twice without your foot on brake to put vehicle in RUN position. This will activate the in
tank fuel pump for approximately 30 seconds.
Repeat this process twice to prime the fuel system.
3. Start the engine using the Normal Starting procedure
Úpage 130.
NOTE:The engine may run rough until the air is forced from all
the fuel lines.
NOTE:
 Use of biodiesel mixture in excess of 20% can nega -
tively impact the fuel filter's ability to separate water
from the fuel, resulting in high pressure fuel system
corrosion or damage.
 In addition, commercially available fuel additives are
not necessary for the proper operation of your diesel
engine.
 For extreme cold conditions, "Mopar® Premium Diesel
Fuel Treatment" is recommended to assist with cold
starting.
INTERVENTION REGENERATION
S
TRATEGY — MESSAGE PROCESS FLOW
This engine meets all required diesel engine emissions
standards. To achieve these emissions standards, your
vehicle is equipped with a state-of-the-art engine and
exhaust system. These systems are seamlessly integrated
into your vehicle and managed by the Powertrain Control
Module (PCM). The PCM manages engine combustion to
allow the exhaust system’s catalyst to trap and burn
Particulate Matter (PM) pollutants, with no input or
interaction on your part.
Additionally, your vehicle has the ability to alert you to
additional maintenance required on your vehicle or
engine.
Refer to Instrument Cluster Display for further information
Úpage 108.
DIESEL EXHAUST FLUID
Diesel Exhaust Fluid (DEF) sometimes known simply by
the name of its active component, UREA—is a key
component of Selective Catalytic Reduction (SCR)
systems, which help diesel vehicles meet stringent
emission regulations. DEF is a liquid reducing agent that
WARNING!
Do not open the high pressure fuel system with the
engine running. Engine operation causes high fuel
pressure. High pressure fuel spray can cause serious
injury or death.
CAUTION!
The starter motor will engage for approximately
30 seconds at a time. Allow two minutes between
cranking intervals.
WARNING!
Do not use alcohol or gasoline as a fuel blending agent.
They can be unstable under certain conditions and be
hazardous or explosive when mixed with diesel fuel.
CAUTION!
Due to lack of lubricants in alcohol or gasoline, the use
of these fuels can cause damage to the fuel system.WARNING!
A hot exhaust system can start a fire if you park over
materials that can burn. Such materials might be grass
or leaves coming into contact with your exhaust system.
Do not park or operate your vehicle in areas where your
exhaust system can contact anything that can burn.
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324SERVICING AND MAINTENANCE
reacts with engine exhaust in the presence of a catalyst to
convert smog-forming Nitrogen Oxides (NOx) into
harmless nitrogen and water vapor.
For further information
Úpage 374.
ACCESSORY DRIVE BELT INSPECTION
When inspecting accessory drive belts, small cracks that
run across the ribbed surface of the belt, from rib to rib,
are considered normal. These are not a reason to replace
a belt. However, cracks running along a rib (not across) are
not normal. Any belt with cracks running along a rib must
be replaced. Also have the belt replaced if it has excessive
wear, frayed cords, or severe glazing.

Accessory Belt (Serpentine Belt)

Conditions that would require replacement:
Rib chunking (one or more ribs has separated from belt
body)
 Rib or belt wear
 Longitudinal belt cracking (cracks between two ribs)
 Belt slips
 Groove jumping (belt does not maintain correct posi -
tion on pulley)
 Belt broken
 Noise (objectionable squeal, squeak, or rumble is
heard or felt while drive belt is in operation)
NOTE:Identify and correct problem before new belt is installed.
Some conditions can be caused by a faulty component
such as a belt pulley. Belt pulleys should be carefully
inspected for damage and proper alignment.
Belt replacement on some models requires the use of
special tools, we recommend having your vehicle serviced
at an authorized dealer.
AIR CONDITIONER MAINTENANCE
For best possible performance, your air conditioner 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!
Do not attempt to inspect an accessory drive belt
with the vehicle running.
 When working near the radiator cooling fan, discon -
nect the fan motor lead. The fan is temperature
controlled and can start at any time regardless of
ignition mode. You could be injured by the moving
fan blades.
 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
service job, take your vehicle to a competent
mechanic.WARNING!
Use only refrigerants and compressor lubricants
approved by the manufacturer for your air condi -
tioning system. Some unapproved refrigerants are
flammable and can explode, injuring you. Other
unapproved refrigerants or lubricants can cause the
system to fail, requiring costly repairs. Refer to
Warranty Information Book, located in your owner’s
information kit, for further warranty information.
 The air conditioning system contains refrigerant
under high pressure. To avoid risk of personal injury
or damage to the system, adding refrigerant or any
repair requiring lines to be disconnected should be
done by an experienced technician.
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.

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SERVICING AND MAINTENANCE325
Refrigerant Recovery And Recycling —
R–1234yf
R–1234yf Air Conditioning Refrigerant is a Hydrofluo -
roolefin (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 recovery and recycling
equipment.
NOTE:Use only the manufacturer approved A/C system PAG
compressor oil, and refrigerants.
Cabin Air Filter
The cabin 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 up on the glove compartment travel stop and lower the door.

Glove Compartment Travel Stop

3. Pivot the glove compartment downward.
4. Disengage the two retaining tabs that secure the air filter access door to the HVAC housing.

Air Filter Retaining Tabs

5. Remove the air filter from the HVAC air inlet housing. Pull the filter elements out pinching them to the right
for clearance.

Air Filter

6. Install the cabin air filter with the air filter position indicators pointing in the same direction as removal.
7. Close cabin air filter access door and secure retaining tabs.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.
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.
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328SERVICING AND MAINTENANCE
(Continued)
(Continued)
Installing The Rear Wiper

1. Lift the wiper arm off of the glass.

2. Insert the wiper blade pivot pin into the opening on
the end of the wiper arm and rotate the wiper in to
place.
3. Place with wiper on the glass and close the tail gate.
EXHAUST SYSTEM
The best protection against carbon monoxide entry into
the vehicle body is a properly maintained engine exhaust
system.
If you notice a change in the sound of the exhaust system;
or if the exhaust fumes can be detected inside the vehicle;
or when the underside or rear of the vehicle is damaged;
have an authorized technician inspect the complete
exhaust system and adjacent body areas for broken,
damaged, deteriorated, or mispositioned parts. Open
seams or loose connections could permit exhaust fumes
to seep into the passenger compartment. In addition, have
the exhaust system inspected each time the vehicle is
raised for lubrication or oil change. Replace as required.
Under normal operating conditions, the catalytic converter
will not require maintenance. However, it is important to
keep the engine properly tuned to ensure proper catalyst
operation and prevent possible catalyst damage.
NOTE:Intentional tampering with emissions control systems can
result in civil penalties being assessed against you.
In unusual situations involving grossly malfunctioning
engine operation, a scorching odor may suggest severe
and abnormal catalyst overheating. If this occurs, stop the
vehicle, turn off the engine and allow it to cool. Service,
including a tune-up to manufacturer's specifications,
should be obtained immediately.
To minimize the possibility of catalytic converter damage:
Do not interrupt the ignition when the transmission is
in gear and the vehicle is in motion.
 Do not try to start the vehicle by pushing or towing the
vehicle.
 Do not idle the engine with any ignition components
disconnected or removed, such as when diagnostic
testing, or for prolonged periods during very rough idle
or malfunctioning operating conditions.
COOLING SYSTEM
WARNING!
Exhaust gases can injure or kill. They contain Carbon
Monoxide (CO), which is colorless and odorless.
Breathing it can make you unconscious and can
eventually poison you
Úpage 288.
A hot exhaust system can start a fire if you park over
materials that can burn. Such materials might be
grass or leaves coming into contact with your
exhaust system. Do not park or operate your vehicle
in areas where your exhaust system can contact
anything that can burn.
CAUTION!
The catalytic converter requires the use of unleaded
fuel only. Leaded gasoline will destroy the effective -
ness of the catalyst as an emissions control device
and may seriously reduce engine performance and
cause serious damage to the engine.
 Damage to the catalytic converter can result if your
vehicle is not kept in proper operating condition. In
the event of engine malfunction, particularly
involving engine misfire or other apparent loss of
performance, have your vehicle serviced promptly.
Continued operation of your vehicle with a severe
malfunction could cause the converter to overheat,
resulting in possible damage to the converter and
vehicle.
WARNING!
WARNING!
You or others can be badly burned by hot engine
coolant (antifreeze) or steam from your radiator. If
you see or hear steam coming from under the hood,
do not open the hood until the radiator has had time
to cool. Never open a cooling system pressure cap
when the radiator or coolant bottle is hot.
 Keep hands, tools, clothing, and jewelry away from
the radiator cooling fan when the hood is raised. The
fan starts automatically and may start at any time,
whether the engine is running or not.

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SERVICING AND MAINTENANCE329
Coolant Checks
Check the engine, battery (if equipped), intercooler (if
equipped), and Motor Generator Unit (MGU) (if equipped)
coolant (antifreeze) protection every 12 months (before
the onset of freezing weather, where applicable). If the
engine, battery (if equipped), intercooler (if equipped), and
MGU (if equipped) coolant is dirty or rusty in appearance,
the system should be drained, flushed and refilled with
fresh OAT coolant (conforming to MS.90032) by an
authorized dealer. Check the front of the A/C condenser (if
equipped) or radiator for any accumulation of bugs,
leaves, etc. If dirty, clean 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, battery (if equipped), intercooler (if
equipped), and MGU (if equipped) cooling system hoses
for brittle rubber, cracking, tears, cuts, and tightness of
the connection at the coolant recovery bottle and radiator.
Inspect the entire system for leaks. DO NOT REMOVE THE
COOLANT PRESSURE CAP WHEN THE COOLING SYSTEM IS
HOT.
Cooling System — Drain, Flush And Refill
NOTE: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.
If the engine coolant (antifreeze) is dirty or contains visible
sediment, have an authorized dealer clean and flush with
OAT coolant (conforming to MS.90032).
For the proper maintenance intervals, see
Úpage 307 for
gasoline engines or Úpage 311 for diesel engines.
Selection Of Coolant
For further information Úpage 374.
NOTE:
 Mixing of engine coolant (antifreeze) other than speci-
fied Organic Additive Technology (OAT) engine coolant,
may result in engine damage and may decrease corro -
sion protection. OAT engine coolant is different and
should not be mixed with Hybrid Organic Additive Tech -
nology (HOAT) engine coolant or any “globally compat -
ible” coolant. If a non-OAT engine coolant is introduced
into the cooling system in an emergency, the cooling
system will need to be drained, flushed, and refilled
with fresh OAT coolant (conforming to MS.90032), by
an authorized dealer as soon as possible.
 Do not use water alone or alcohol-based engine
coolant (antifreeze) products. Do not use additional
rust inhibitors or anti-rust products, as they may not be
compatible with the radiator engine coolant and may
plug the radiator.
 This vehicle has not been designed for use with
propylene glycol-based engine coolant. Use of
propylene glycol-based engine coolant is not recom -
mended. 
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.
Adding Coolant

Your vehicle has been built with an improved engine coolant
(OAT coolant conforming to MS.90032) that allows
extended maintenance intervals. This engine coolant
(antifreeze) can be used up to 10 years or 150,000 miles
(240,000 km) before replacement. To prevent reducing this
extended maintenance period, it is important to use the
same engine coolant (OAT coolant conforming to
MS.90032) throughout the life of your vehicle.

Please review these recommendations for using Organic
Additive Technology (OAT) engine coolant that meets the
requirements of the manufacturer Material Standard
MS.90032. When adding engine coolant (antifreeze):
We recommend using Mopar® Antifreeze/Coolant
10 Year/150,000 Mile (240,000 km) Formula OAT
(Organic Additive Technology) that meets the require -
ments of the manufacturer Material Standard
MS.90032.
 Mix a minimum solution of 50% OAT engine coolant
that meets the requirements of the manufacturer
Material Standard MS.90032 and distilled water. Use
higher concentrations (not to exceed 70%) if tempera -
tures below −34°F (−37°C) are anticipated. Please
contact an authorized dealer for assistance.
 Use only high purity water such as distilled or deionized
water when mixing the water/engine coolant solution.
The use of lower quality water will reduce the amount
of corrosion protection in the engine cooling system.

When working near the radiator cooling fan, discon -
nect the fan motor lead or turn the ignition to the OFF
mode. The fan is temperature controlled and can
start at any time the ignition is in the ON mode.
WARNING!
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