engine coolant JEEP WRANGLER 2023 User Guide

308SERVICING AND MAINTENANCE
Mileage Or Time Passed (Whichever Comes
First):
20,000
30,000
40,000
50,000
60,000
70,000
80,000
90,000
100,000
110,000
120,000
130,000
140,000
150,000
Or Years: 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Or Kilometers:
32,000
48,000
64,000
80,000
96,000
112,000
128,000
144,000
160,000
176,000
192,000
208,000
224,000
240,000
Additional Inspections
Inspect the CV/Universal joints. X X X X X X X X X X X X X X
Inspect front suspension, tie rod ends, rear suspension,
and replace if necessary. X
XXXXXX
Inspect the front and rear axle fluid. XXXX
Inspect the brake linings, replace as necessary. XXXXXXX
Adjust parking brake on vehicles equipped with four
wheel disc brakes. X
XXXXXX
Inspect transfer case fluid. XXX
Additional Maintenance
Replace engine air cleaner filter. XXXXX
Replace cabin air filter. To be replaced every 12,000 miles (19,000 km).
Replace Spark Plugs – 2.0L Engine.
1X X
Replace spark plugs – 3.6L Engine.
1X
Flush and replace the engine, intercooler
(if equipped) coolant at 10 years or
150,000 miles (240,000 km) whichever comes first. X
X

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310SERVICING AND MAINTENANCE
SCHEDULED SERVICING — DIESEL ENGINE
Your vehicle is equipped with an automatic oil change
indicator system. The oil change indicator system will
remind you that it is time to take your vehicle in for
scheduled maintenance.
Based on engine operation conditions, the oil change
indicator message will illuminate. This means that service
is required for your vehicle. Operating conditions such as
frequent short-trips, trailer tow, extremely hot or cold
ambient temperatures will influence when the “Oil Change
Required” message is displayed. Have your vehicle
serviced as soon as possible, within the next 500 miles
(805 km).
An authorized dealer will reset the oil change indicator
message after completing the scheduled oil change. If a
scheduled oil change is performed by someone other than
an authorized dealer, to reset the message
Úpage 108.
NOTE:Under no circumstances should oil change intervals
exceed 10,000 miles (16,000 km) or 12 months,
whichever comes first.
Engine Oil Filter Replacement
Residual oil in the housing may spill from the housing
when the new filter is installed if the residual oil is not
either removed from the housing or enough time has not
elapsed to allow the oil to drain back into the engine.
When servicing the oil filter on this engine, open the filter
cap approximately six turns until the cap o-ring is visible
and stop. Wait five minutes with the cap in this position to
allow dirty engine oil to drain back into the engine. After
five minutes, the cap and filter assembly can be removed
and discarded. When installing the new oil filter cartridge
assembly, ensure the cap is tightened to the specified
torque to prevent low oil pressure conditions. Once A Month Or Before A Long Trip:

Check engine oil level
 Check windshield washer fluid level
 Check the tire pressures and look for unusual wear or
damage
 Check the fluid levels of the coolant reservoir, brake
master cylinder, and fill as needed
 Check function of all interior and exterior lights

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SERVICING AND MAINTENANCE313
ADDITIONAL MAINTENANCE — B6 TO B20 BIODIESEL
NOTE:
Under no circumstances should oil change intervals exceed 8,000 miles (12,875 km) or six months, whichever comes first when using biodiesel blends greater than 5% (B5).
 The owner is required to monitor mileage for B6-B20 biodiesel, the automatic oil change indicator system does not reflect the use of biofuels.
 Fuel filter change interval is maintained at every second oil change. This is especially important with biodiesel usage.
For more information on using biodiesel
Úpage 371.
Flush and replace the engine coolant at 10 years or 150,000 miles
(240,000 km) whichever comes first.
X
X
Replace accessory drive belt(s). X
Change transfer case fluid. X
Mileage Or Time Passed (Whichever Comes First)
10,000
20,000
30,000
40,000
50,000
60,000
70,000
80,000
90,000
100,000
110,000
120,000
130,000
140,000
150,000
Or Years: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Or Kilometers:
16,000
32,000
48,000
64,000
80,000
96,000
112,000
128,000
144,000
160,000
176,000
192,000
208,000
224,000
240,000
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 competent mechanic.
 Failure to properly inspect and maintain your vehicle could result in a component malfunction and affect vehicle handling and performance. This could cause an accident.
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314SERVICING AND MAINTENANCE
ENGINE COMPARTMENT
2.0L GASOLINE ENGINE
1 — Battery 6 — Brake Fluid Reservoir Cap
2 — Power Distribution Center (Fuses) 7 — Washer Fluid Reservoir Cap
3 — Engine Oil Dipstick 8 — Engine Air Cleaner Filter
4 — Engine Oil Fill 9 — Power Steering Reservoir Cap
5 — Engine Coolant Pressure Cap 10 — Intercooler Coolant Reservoir Cap

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SERVICING AND MAINTENANCE315
3.6L GASOLINE ENGINE
1 — Power Distribution Center (Fuses) 7 — Power Pack Unit Pressure Cap — If Equipped
2 — Battery 8 — Washer Fluid Reservoir Cap
3 — Engine Oil Dipstick 9 — Engine Air Cleaner Filter
4 — Engine Oil Fill 10 — Power Steering Reservoir Cap
5 — Engine Coolant Pressure Cap 11 — Motor Generator Unit Coolant Pressure Cap— If Equipped
6 — Brake Fluid Reservoir Cap
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316SERVICING AND MAINTENANCE
3.0L DIESEL ENGINE
1 — Battery 6 — Power Distribution Center (Fuses)
2 — Engine Oil Fill 7 — Power Steering Reservoir Cap
3 — Engine Coolant Pressure Reservoir Cap 8 — Engine Oil Dipstick
4 — Brake Fluid Reservoir Cap 9 — Engine Air Cleaner Filter
5 — Washer Fluid Reservoir Cap

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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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