2023 JEEP WRANGLER engine

322SERVICING AND MAINTENANCE

1. Ensure engine is turned off.

2. Remove the fuel filter protective cover to access the
fuel filter assembly.

Fuel Filter Assembly

3. Place drain pan under the fuel filter assembly.
4. Open the water drain valve, and let any accumulated water and fuel drain.
5. Close the water drain valve.

Fuel Filter Assembly

6. Wipe clean the underside of the filter housing to prevent contamination from entering fuel system
during service.
7. Remove the fuel filter cap and filter from the housing using a socket. Rotate counterclockwise for removal.

Fuel Filter Assembly

8. Remove the used fuel filter cartridge from the cap and dispose of according to your local regulations.
9. Wipe clean the sealing surfaces of the cap and housing.
1 — Retainers
2 — Fuel Filter Protective Cover
1 — Water Drain Valve1 — Fuel Filter Cap
2 — Socket Adapter
CAUTION!
Take care when handling the new fuel filter to prevent
contamination from entering the fuel system.

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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.
8

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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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326SERVICING AND MAINTENANCE
8. Rotate the glove compartment door back into
position ensuring you have properly engaged the
travel dampener.

Travel Dampener

For the proper maintenance intervals, see Úpage 307 for
gasoline engines or Úpage 311 for diesel engines.
BODY LUBRICATION
Locks and all body pivot points, including such items as
seat tracks, door hinge pivot points and rollers, liftgate,
tailgate, decklid, sliding doors and hood hinges, should be
lubricated periodically with a lithium based grease, such
as Mopar® Spray White Lube to ensure quiet, easy
operation and to protect against rust and wear. Prior to the
application of any lubricant, the parts concerned should
be wiped clean to remove dust and grit; after lubricating
excess oil and grease should be removed. Particular
attention should also be given to hood latching components to ensure proper function. When performing
other underhood services, the hood latch release
mechanism, and safety catch should be cleaned and
lubricated.
The external lock cylinders should be lubricated twice a
year, preferably in the Fall and Spring. Apply a small
amount of a high quality lubricant, such as Mopar® Lock
Cylinder Lubricant directly into the lock cylinder.
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 products such as engine oil, gasoline, etc.
NOTE:Life expectancy of wiper blades varies depending on
geographical area and frequency of use. Poor perfor
-
mance 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
 Hardening or cracking
 Deformation or fatigue
If a wiper blade or wiper arm is damaged, replace the
affected wiper arm or blade with a new unit. Do not
attempt to repair a wiper arm or blade that is damaged.
Wiper Blade Removal/Installation

1. Lift the wiper arm to raise the wiper blade off of the glass, until the wiper arm is in the full up position.

Wiper Blade With Release Tab In Locked Position

1 — Travel Dampener Housing
2 — Travel Dampener Rod
CAUTION!
Do not allow the wiper arm to spring back against the
glass without the wiper blade in place or the glass may
be damaged.
1 — Wiper Blade
2 — Wiper Arm
3 — Release Tab

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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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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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