service JEEP WRANGLER UNLIMITED 2013 Service Manual

General Information
This device complies with part 15 of the FCC rules and
RSS 210 of Industry Canada. Operation is subject to the
following conditions:
• This device may not cause harmful interference.
• This device must accept any interference received,
including interference that may cause undesired op-
eration.
The tire pressure sensors are covered under one of the
following licenses:
United States MRXC4W4MA4
Canada 2546A-C4W4MA4 FUEL REQUIREMENTS
3.6L Engine
This engine is designed to meet all emis-
sions regulations and provide excellent fuel
economy and performance when using
high-quality unleaded “regular” gasoline
having an octane rating of 87. The use of
premium gasoline is not recommended, as it will not
provide any benefit over regular gasoline in these engines.
Light spark knock at low engine speeds is not harmful to
your engine. However, continued heavy spark knock at
high speeds can cause damage and immediate service is
required. Poor quality gasoline can cause problems such
as hard starting, stalling, and hesitations. If you experi-
ence these symptoms, try another brand of gasoline
before considering service for the vehicle.506 STARTING AND OPERATING

can be used at levels higher than those allowed in the
United States. MMT is prohibited in Federal and Califor-
nia reformulated gasoline.
Materials Added To Fuel
All gasoline sold in the United States is required to contain
effective detergent additives. Use of additional detergents
or other additives is not needed under normal conditions
and they would result in additional cost. Therefore, you
should not have to add anything to the fuel.
Fuel System Cautions
CAUTION!Follow these guidelines to maintain your vehicle’s
performance:
• The use of leaded gas is prohibited by Federal law.
Using leaded gasoline can impair engine perfor-
mance and damage the emissions control system. (Continued) CAUTION! (Continued)• An out-of-tune engine or certain fuel or ignition
malfunctions can cause the catalytic converter to
overheat. If you notice a pungent burning odor or
some light smoke, your engine may be out of tune or
malfunctioning and may require immediate service.
Contact your authorized dealer for service assistance.
• The use of fuel additives, which are now being sold
as octane enhancers, is not recommended. Most of
these products contain high concentrations of metha-
nol. Fuel system damage or vehicle performance
problems resulting from the use of such fuels or
additives is not the responsibility of the manufac-
turer.
NOTE: Intentional tampering with the emissions control
system can result in civil penalties being assessed against
you.
5 STARTING AND OPERATING 509

CAUTION!Driving with a hot cooling system could damage your
vehicle. If the temperature gauge reads HOT (H), pull
over and stop the vehicle. Idle the vehicle with the air
conditioner turned off until the pointer drops back
into the normal range. If the pointer remains on HOT
(H), and you hear continuous chimes, turn the engine
off immediately, and call for service.
NOTE: There are steps that you can take to slow down
an impending overheat condition:
• If your air conditioner (A/C) is on, turn it off. The A/C
system adds heat to the engine cooling system and
turning the A/C off can help remove this heat. • You can also turn the temperature control to maximum
heat, the mode control to floor and the blower control
to high. This allows the heater core to act as a
supplement to the radiator and aids in removing heat
from the engine cooling system.
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 try to open a cooling system pressure
cap when the radiator or coolant bottle is hot.
6 WHAT TO DO IN EMERGENCIES 539

JACKING AND TIRE CHANGING
WARNING!• Do not attempt to change a tire on the side of the
vehicle close to moving traffic. Pull far enough off
the road to avoid the danger of being hit when
operating the jack or changing the wheel.
• Being under a jacked-up vehicle is dangerous. The
vehicle could slip off the jack and fall on you. You
could be crushed. Never put any part of your body
under a vehicle that is on a jack. If you need to get
under a raised vehicle, take it to a service center
where it can be raised on a lift. (Continued) WARNING! (Continued)• Never start or run the engine while the vehicle is
on a jack.
• The jack is designed to be used as a tool for
changing tires only. The jack should not be used to
lift the vehicle for service purposes. The vehicle
should be jacked on a firm level surface only.
Avoid ice or slippery areas.540 WHAT TO DO IN EMERGENCIES

Jacking Instructions
WARNING!Carefully follow these tire changing warnings to
help prevent personal injury or damage to your
vehicle:
• Always park on a firm, level surface as far from the
edge of the roadway as possible before raising the
vehicle.
• Turn on the Hazard Warning flasher.
• Block the wheel diagonally opposite the wheel to
be raised.
• Set the parking brake firmly and set an automatic
transmission in PARK; a manual transmission in
REVERSE.
• Never start or run the engine with the vehicle on a
jack. (Continued) WARNING! (Continued)• Do not let anyone sit in the vehicle when it is on a
jack.
• Do not get under the vehicle when it is on a jack. If
you need to get under a raised vehicle, take it to a
service center where it can be raised on a lift.
• Only use the jack in the positions indicated and for
lifting this vehicle during a tire change.
• If working on or near a roadway, be extremely
careful of motor traffic.
• To assure that spare tires, flat or inflated, are
securely stowed, spares must be stowed with the
valve stem facing the ground.
6 WHAT TO DO IN EMERGENCIES 543

7. Position the spare wheel/tire on the vehicle and install
the lug nuts with the cone-shaped end toward the
wheel. Lightly tighten the lug nuts clockwise.
WARNING!To avoid the risk of forcing the vehicle off the jack,
do not tighten the lug nuts fully until the vehicle has
been lowered. Failure to follow this warning may
result in personal injury.
8. Lower the vehicle by turning the jack screw to the left,
and remove the jack.
9. Finish tightening the lug nuts. Push down on the
wrench while tightening for increased leverage. Alter-
nate nuts until each nut has been tightened twice. The
correct wheel nut tightness is 95 ft lbs (130 N·m). If in
doubt about the correct tightness, have them checked
with a torque wrench by your authorized dealer or at
a service station.Lug Nut Installation546 WHAT TO DO IN EMERGENCIES

10. Remove the jack assembly and wheel blocks.
11 . Secure the tire, jack, and tools in their proper locations.
12. Remove blocks from wheels.
WARNING!A loose tire or jack thrown forward in a collision or
hard stop, could endanger the occupants of the ve-
hicle. Always stow the jack parts and the spare tire in
the places provided.
Road Tire Installation
1. Mount the road tire on the axle.
2. Install the remaining lug nuts with the cone shaped
end of the nut toward the wheel. Lightly tighten the
lug nuts. WARNING!To avoid the risk of forcing the vehicle off the jack,
do not tighten the lug nuts fully until the vehicle has
been lowered. Failure to follow this warning may
result in personal injury.
3. Lower the vehicle to the ground by turning the jack
handle counterclockwise.
4. Finish tightening the lug nuts. Push down on the
wrench while at the end of the handle for increased
leverage. Tighten the lug nuts in a star pattern until each
nut has been tightened twice. The correct tightness of
each lug nut is 95 ft/lbs (130 N·m). If in doubt about the
correct tightness, have them checked with a torque
wrench by your authorized dealer or service station.
5. After 25 miles (40 km) check the lug nut torque with a
torque wrench to ensure that all lug nuts are properly
seated against the wheel.
6 WHAT TO DO IN EMERGENCIES 547

TOWING A DISABLED VEHICLE
This section describes procedures for towing a disabled
vehicle using a commercial wrecker service. If the trans-
mission and drivetrain are operable, disabled vehicles
may also be towed as described under “Recreational
Towing” in the “Starting And Operating” section.
Towing Condition Wheels OFF the Ground 4WD MODELS
Flat Tow NONE See instructions under “Recreational Towing”
• Automatic Transmission in PARK
• Manual Transmission in gear
( NOT in Neutral)
• Transfer Case in NEUTRAL
• To w i n forward direction
Wheel Lift or Dolly Tow Front NOT ALLOWED
Rear NOT ALLOWED
Flatbed ALL BEST METHOD556 WHAT TO DO IN EMERGENCIES

MAINTAINING YOUR VEHICLECONTENTS  ENGINE COMPARTMENT — 3.6L ......... .561
 ONBOARD DIAGNOSTIC SYSTEM — OBD II . .562
▫ Loose Fuel Filler Cap Message ........... .562
 EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS ......................... .563
 REPLACEMENT PARTS ................. .564
 DEALER SERVICE ..................... .564
 MAINTENANCE PROCEDURES .......... .565
▫ Engine Oil ......................... .566
▫ Engine Oil Filter ..................... .569 ▫ Engine Air Cleaner Filter ............... .569
▫ Maintenance-Free Battery .............. .570
▫ Air Conditioner Maintenance ............ .571
▫ Body Lubrication .................... .572
▫ Windshield Wiper Blades .............. .573
▫ Adding Washer Fluid ................. .574
▫ Exhaust System ..................... .574
▫ Cooling System ..................... .577
▫ Brake System ....................... .583
▫ Automatic Transmission – If Equipped ..... .585
7

ONBOARD DIAGNOSTIC SYSTEM — OBD II
Your vehicle is equipped with a sophisticated onboard
diagnostic system called OBD II. This system monitors
the performance of the emissions, engine, and automatic
transmission control systems. When these systems are
operating properly, your vehicle will provide excellent
performance and fuel economy, as well as engine emis-
sions well within current government regulations.
If any of these systems require service, the OBD II system
will turn on the “Malfunction Indicator Light” (MIL). It
will also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be drivable and not
need towing, see your authorized dealer for service as
soon as possible. CAUTION!• Prolonged driving with the MIL on could cause
further damage to the emission control system. It
could also affect fuel economy and drivability. The
vehicle must be serviced before any emissions tests
can be performed.
• If the MIL is flashing while the engine is running,
severe catalytic converter damage and power loss
will soon occur. Immediate service is required.
Loose Fuel Filler Cap Message
After fuel is added, the vehicle diagnostic system can
determine if the fuel filler cap is possibly loose, improp-
erly installed, or damaged. A “gASCAP” message will be
displayed in the odometer. Tighten the gas cap until a
 clicking  sound is heard. This is an indication that the562 MAINTAINING YOUR VEHICLE