2023 JEEP WRANGLER engine

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
8

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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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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.
8

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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.

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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

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320SERVICING AND MAINTENANCE
3. Remove the engine air cleaner filter from the housing
assembly.

Engine Air Cleaner Filter Cover

Engine Air Cleaner Filter Installation
NOTE:Inspect and clean the housing if significant dirt or debris is
present before replacing the engine air cleaner filter.

1. Install the engine air cleaner filter into the housing assembly with the engine air cleaner filter
inspection surface facing downward.

2. Tighten engine air cleaner filter cover fasteners using a suitable tool.
Engine Air Cleaner Filter Inspection and
Replacement — Diesel 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.
3. Remove the engine air cleaner filter from the housing assembly.

Engine Air Cleaner Filter

Engine Air Cleaner Filter Installation
NOTE:Inspect and clean the housing if significant dirt or debris is
present before replacing the engine air cleaner filter.

1. Install the engine air cleaner filter into the housing assembly with the engine air cleaner filter
inspection surface facing downward.

2. Tighten engine air cleaner filter cover fasteners using a suitable tool.
CAUTION!
Do not overtighten the engine air cleaner filter cover lid
screws or damage may result.
1 — Engine Air Cleaner Filter Cover
2 — Fasteners
1 — Engine Air Cleaner Filter Cover
2 — Engine Air Cleaner Filter
CAUTION!
Do not overtighten the engine air cleaner filter cover lid
screws or damage may result.

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SERVICING AND MAINTENANCE321
DRAINING FUEL/WATER SEPARATOR
F
ILTER — DIESEL ENGINE
The fuel/water separator housing is located inside the left
frame rail in front of the fuel tank. The best access to this
water drain valve is from under the vehicle.
If necessary remove the fuel filter protective cover to
access the water drain valve.

Fuel/Water Separator Filter

If water is detected in the water separator while the engine
is running, or while the ignition switch is in the ON position,
the Water In Fuel Indicator Light will illuminate and an
audible chime will be heard. At this point you should stop
the engine and drain the water from the filter housing.

Fuel/Water Separator Filter

Within 10 minutes of vehicle shutdown, turn the filter
drain valve (located on the bottom of the filter housing)
counterclockwise to drain fuel/water; allow the
accumulated water to drain. Leave the drain valve open
until all water and contaminants have been removed.
When clear fuel is visible, close the drain valve by turning
it clockwise.
Upon proper draining of the water from fuel filter
assembly, the Water In Fuel Indicator Light will remain
illuminated for approximately 10 seconds. If the water was
drained while the engine was running, the Water In Fuel
Indicator Light may remain on for approximately three
minutes.
NOTE:Care should be taken in disposing of used fluids from your
vehicle. Used fluids, indiscriminately discarded, can
present a problem to the environment. Contact an autho-
rized dealer, service station, or government agency for
advice on recycling programs and for where used fluids
and filters can be properly disposed of in your area.
If more than two ounces or 60 ml of fuel have been
drained, follow the directions for Priming If The Engine Has
Run Out Of Fuel
Úpage 323.
FUEL FILTER REPLACEMENT — DIESEL
E
NGINE
NOTE:Using a fuel filter that does not meet the manufacturer’s
filtration and water separating requirements can severely
impact fuel system life and reliability. We recommend you
use Mopar® Fuel Filter. Must meet 3 micron rating.
CAUTION!
 Do not drain the fuel/water separator filter when the
engine is running.
 Diesel fuel will damage blacktop paving surfaces.
Drain the filter into an appropriate container.
1 — Retainers
2 — Fuel Filter Protective Cover
1 — Water In Fuel Drain Valve
CAUTION!
 Diesel fuel will damage blacktop paving surfaces.
Drain the filter into an appropriate container.
 Do not prefill the fuel filter when installing a new fuel
filter. There is a possibility debris could be introduced
into the fuel filter during this action. It is best to
install the filter dry and allow the in-tank lift pump to
prime the fuel system.8

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