Jeep Wrangler (2018 year). Manual — part 27

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
Procedure” 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 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 con-

tain lead and lead compounds. 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

(Continued)

CAUTION! (Continued)

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.

DEALER SERVICE

An authorized dealer has the qualified service personnel,

special tools, and equipment to perform all service opera-

tions in an expert manner. Service Manuals are available

which include detailed service information for your ve-

hicle. Refer to these Service Manuals before attempting any

procedure yourself.

NOTE:

Intentional tampering with emissions control sys-

tems may void your warranty and could result in civil

penalties being assessed against you.

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SERVICING AND MAINTENANCE

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.

Engine Oil

Change Engine Oil — Gasoline Engine

Refer to “Scheduled Servicing” in this section for the

proper maintenance intervals.

NOTE:

Under no circumstances should oil change inter-

vals exceed 10,000 miles (16,000 km), 12 months or 350

hours of engine run time, whichever comes first. The 350

hours of engine run or idle time is generally only a concern

for fleet customers.

Engine Oil Selection — 2.0L Engine

For best performance and maximum protection under all

types of operating conditions, the manufacturer only rec-

ommends engine oils that are API Certified and meet the

requirements of FCA Material Standard MS-13340.

Engine Oil Selection 3.6L Engine

For best performance and maximum protection under all

types of operating conditions, the manufacturer only rec-

ommends engine oils that are API Certified and meet the

requirements of FCA Material Standard MS-6395.

American Petroleum Institute (API) Engine Oil
Identification Symbol

This symbol means that the oil has

been certified by the American Pe-

troleum Institute (API). The manu-

facturer only recommends API Cer-

tified engine oils.
This symbol certifies 0W-20, 5W-20,

0W-30, 5W-30 and 10W-30 engine

oils.

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 MAINTENANCE

423

Engine Oil Viscosity (SAE Grade) — 2.0L Engine

Mopar SAE 5W-30 engine oil approved to FCA Material

Standard MS-13340 such as Pennzoil, Shell Helix or equiva-

lent is recommended for all operating temperatures. This

engine oil improves low temperature starting and vehicle

fuel economy.
The engine oil filler cap also shows the recommended

engine oil viscosity for your engine. For information on

engine oil filler cap location, refer to the “Engine Compart-

ment” illustration in this section.
Lubricants which do not have both the engine oil certifi-

cation mark and the correct SAE viscosity grade number

should not be used.

Engine Oil Viscosity (SAE Grade) — 3.6L Engine

Mopar SAE 0W-20 engine oil approved to FCA Material

Standard MS-6395 such as Pennzoil, Shell Helix or equiva-

lent is recommended for all operating temperatures. This

engine oil improves low temperature starting and vehicle

fuel economy.
The engine oil filler cap also shows the recommended

engine oil viscosity for your engine. For information on

engine oil filler cap location, refer to the “Engine Compart-

ment” illustration in this section.

Lubricants which do not have both the engine oil certifi-

cation mark and the correct SAE viscosity grade number

should not be used.

Synthetic Engine Oils

You may use synthetic engine oils provided the recom-

mended oil quality requirements are met, and the recom-

mended maintenance intervals for oil and filter changes are

followed.
Synthetic engine oils which do not have both the engine oil

certification mark and the correct SAE viscosity grade

number should not be used.

Materials Added To Engine Oil

The manufacturer strongly recommends against the addi-

tion 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

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SERVICING AND MAINTENANCE

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

This manufacturer’s engines have a full-flow type dispos-

able oil filter. Use a filter of this type for replacement. The

quality of replacement filters varies considerably. Only

high quality filters should be used to assure most efficient

service. Mopar engine oil filters are high quality oil filters

and are recommended.

Engine Air Cleaner Filter

Refer to the “Maintenance Plan” in this section for the

proper maintenance intervals.

NOTE:

Be sure to follow the “Severe Duty Conditions”

maintenance interval if applicable.

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 ve-
hicle with the air induction system (air cleaner, hoses,
etc.) removed. Failure to do so can result in serious
personal injury.

Engine Air Cleaner Filter Selection

The quality of replacement engine air cleaner filters varies

considerably. Only high quality filters should be used to

assure most efficient service. Mopar engine air cleaner

filters are a high quality filter and are recommended.

Engine Air Cleaner Filter Inspection and
Replacement — Gasoline Engine

Follow the recommended maintenance intervals as shown

in the Maintenance Schedule in this section.

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425

Engine Air Cleaner Filter Removal

1. Loosen the retainers from the air cleaner cover using a

suitable tool.

2. Lift the air cleaner cover to access the air cleaner filter.

3. Remove the air cleaner filter element from the housing

assembly.

Air Cleaner Filter Cover

1 — Retainers
2 — Air Filter Cover

Air Cleaner Filter Cover

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SERVICING AND MAINTENANCE

Engine Air Cleaner Filter Installation

NOTE:

Inspect and clean the housing if dirt or debris is

present before replacing the air filter element.
1. Install the air cleaner filter element into the housing

assembly with the air cleaner filter inspection surface

facing downward.

2. Tighten air cleaner cover retainers using a suitable tool.

Accessory Drive Belt Inspection

WARNING!

• Do not attempt to inspect an accessory drive belt

with 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 me-
chanic.

When inspecting accessory drive belts, small cracks that

run across ribbed surface of belt from rib to rib, are

considered normal. These are not a reason to replace 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.

Air Cleaner Filter

1 — Air Cleaner Filter Inspection Surface
2 — Air Cleaner Filter

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427

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 (note: identify and correct problem before

new belt is installed)

• Noise (objectionable squeal, squeak, or rumble is heard

or felt while drive belt is in operation)

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!

• Use only refrigerants and compressor lubricants ap-

proved by the manufacturer for your air conditioning
system. Some unapproved refrigerants are flam-
mable and can explode, injuring you. Other unap-
proved refrigerants or lubricants can cause the sys-
tem to fail, requiring costly repairs. Refer to

(Continued)

Accessory Belt (Serpentine Belt)

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SERVICING AND MAINTENANCE

WARNING! (Continued)

Warranty Information Book, located in your owner’s
information kit, for further warranty information.

• The air conditioning system contains refrigerant un-

der 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 condition-
ing 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 hydrofluoro-

carbon (HFC) that is an ozone-friendly substance. The

manufacturer recommends that air conditioning service be

performed by an authorized dealer or other service facili-

ties 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 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 recom-

mends that air conditioning service be performed by an

authorized dealer using recovery 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.

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SERVICING AND MAINTENANCE

429

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 up on the glove compartment travel stop and

lower the door.

3. Pivot the glove compartment downward.
4. Disengage the two retaining tabs that secure the air filter

access door to the HVAC housing.

5. Remove the air filter from the HVAC air inlet housing.

Pull the filter elements out pinching them to the right for

clearance.

Glove Compartment Travel Stop

Air Filter Retaining Tabs

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SERVICING AND MAINTENANCE

6. Install the A/C air filter with the air filter position

indicators pointing in the same direction as removal.

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.

7. Close A/C Air Filter access door and secure retaining

tabs.

8. Rotate the glove compartment door back into position

ensuring you have properly engaged the travel damper.

Refer to the “Maintenance Plan” in this section for the

proper maintenance intervals.

Air Filter

Travel Dampener

1 — Travel Dampener Housing
2 — Travel Dampener Rod

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431

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 assure quiet, easy operation

and to protect against rust and wear. Prior to the applica-

tion 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 ser-

vices, 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.

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SERVICING AND MAINTENANCE

The wiper blades and wiper arms should be inspected

periodically, not just when wiper performance problems

are experienced. This inspection should include the follow-

ing 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

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. 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 — Wiper Blade
2 — Cover
3 — Wiper Arm
4 — Release Tab

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SERVICING AND MAINTENANCE

433

2. To disengage the wiper blade from the wiper arm, raise

the cover, press the release tab on the wiper blade and

while holding the wiper arm with one hand, slide the

wiper blade down towards the base of the wiper arm.

3. With the wiper blade disengaged, remove the wiper

blade from the wiper arm.

4. Gently lower the wiper arm onto the glass.

Installing The Front Wipers

1. Lift the wiper arm off of the glass, until the wiper arm is

in the full up position.

2. Position the wiper blade near the hook on the tip of the

wiper arm.

3. Insert the hook on the tip of the arm through the

opening in the wiper blade.

4. Slide the wiper blade up into the hook on the wiper arm,

latch engagement will be accompanied by an audible

click then close the cover.

5. Gently lower the wiper blade onto the glass.

Wiper Blade With Release Tab In Unlocked Position

1 — Wiper Blade
2 — Wiper Arm J Hook
3 — J Hook Retainer
4 — Cover

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SERVICING AND MAINTENANCE

Rear Wiper Blade Removal/Installation

1. Open tailgate to access the wiper arm.

2. Lift wiper arm off of the glass and rotate wiper blade

outward to disengage the wiper blade from the wiper

arm.

3. Gently set the arm on the glass.

Rear Wiper Assembly

1 — Wiper Arm
2 — Wiper Blade

Wiper Blade And Wiper Arm

1 — Wiper Arm
2 — Wiper Blade

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435

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 ex-

haust system and adjacent body areas for broken, dam-

aged, 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 lubri-

cation or oil change. Replace as required.

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. To avoid breathing CO, refer
to “Safety Tips” in “Safety” for further information.

(Continued)

Wiper Blade Removed From Wiper Arm

1 — Wiper Blade Pivot Pin
2 — Wiper Arm Receptacle

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SERVICING AND MAINTENANCE

WARNING! (Continued)

• 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 involv-
ing engine misfire or other apparent loss of perfor-
mance, have your vehicle serviced promptly. Contin-
ued operation of your vehicle with a severe
malfunction could cause the converter to overheat,
resulting in possible damage to the converter and
vehicle.

Under normal operating conditions, the catalytic converter

will not require maintenance. However, it is important to

keep the engine properly tuned to assure proper catalyst

operation and prevent possible catalyst damage.

NOTE:

Intentional tampering with emissions control sys-

tems 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.

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