2007 JEEP WRANGLER maintenance

CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures have
been established for the tire size equipped on your
vehicle. Undesirable system operation or sensor
damage may result when using replacement equip-
ment that is not of the same size, type, and/or style.
After-market wheels can cause sensor damage. Do
not use tire sealant from a can, or balance beads if
your vehicle is equipped with a TPMS, as damage to
the sensors may result.
CAUTION!
After inspecting or adjusting the tire pressure always
reinstall the valve stem cap. This will prevent mois-
ture and dirt from entering the valve stem, which
could damage the wheel rim sensor.
NOTE:
•The TPMS is not intended to replace normal tire care
and maintenance, nor to provide warning of a tire
failure or condition.
•The TPMS should not be used as a tire pressure gauge
while adjusting your tire pressure.
•Driving on a significantly under-inflated tire causes
the tire to overheat and can lead to tire failure.
320 STARTING AND OPERATING

Consider the following items when computing the
weight on the rear axle of the vehicle:
•The tongue weight of the trailer.
•The weight of any other type of cargo or equipment
put in or on your vehicle.
•The weight of the driver and all passengers.
NOTE:Remember that everything put into or on the
trailer adds to the load on your vehicle. Also, additional
factory-installed options, or dealer-installed options,
must be considered as part of the total load on your
vehicle. Refer to the Tire and Loading Information plac-
ard in the Tire Safety Information section of this manual
for the maximum combined weight of occupants and
cargo for your vehicle.
Towing Requirements
To promote proper break-in of your new vehicle driv-
etrain components the following guidelines are recom-
mended:
NOTE:Trailer towing requires special rear axle lubri-
cant. Refer to “Fluids, Lubricants, and Genuine Parts” in
Section 7 for more information.
CAUTION!
•Avoid towing a trailer for the first 500 miles (805
km) of vehicle operation. Doing so may damage
your vehicle.
Perform the maintenance listed in Section 8 of this
manual. When towing a trailer, never exceed the GAWR,
or GCWR, ratings.
STARTING AND OPERATING 339
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The automatic transmission fluid and filter should be
changed if you REGULARLY tow a trailer for more than
45 minutes of continuous operation. See “Schedule B” in
section 8 of this manual for transmission fluid change
intervals.
NOTE:Check the automatic transmission fluid level
before towing.
Towing Tips — O/D Off (If Equipped)
To reduce potential for automatic transmission overheat-
ing, turn the “O/D OFF” feature OFF when driving in
hilly areas or shift the transmission to Drive position 2 on
more severe grades. Refer to “Transmission Shifting” in
this section.
Towing Tips — Electronic Speed Control (If
Equipped)

Don’t use in hilly terrain or with heavy loads.
When using the speed control, if you experience speed
drops greater than 10 mph (16 km/h), disengage until
you can get back to cruising speed.
Use speed control in flat terrain and with light loads to
maximize fuel efficiency.
Towing Tips — Cooling System
To reduce potential for engine and transmission over-
heating, take the following actions:
Highway Driving
Reduce speed.
Air Conditioning
Turn off temporarily.
refer to Cooling System Operating information in the
Maintenance section of this manual for more informa-
tion.
STARTING AND OPERATING 345
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MAINTAINING YOUR VEHICLE
CONTENTS
Engine Compartment – 3.8L...............364
Onboard Diagnostic System — OBD II........365
▫Loose Fuel Filler Cap Message............366
Emissions Inspection And Maintenance
Programs............................366
Replacement Parts......................368
Dealer Service.........................368
Maintenance Procedures..................369
▫Engine Oil..........................369▫Drive Belts — Check Condition And Tension . . 372
▫Spark Plugs.........................373
▫Catalytic Converter....................373
▫Crankcase Emission Control System........375
▫Fuel Filter..........................375
▫Engine Air Cleaner Filter................375
▫Maintenance-Free Battery................376
▫Air Conditioner Maintenance.............376
▫Power Steering Fluid Check..............377
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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 loose fuel filler cap message
will be displayed in the instrument cluster. Tighten the
gas cap until aclickingsound is heard. This is an
indication that the gas cap is properly tightened. Press
the odometer reset button to turn the message off. If the
problem persists, the message will appear the next time
the vehicle is started. This might indicate a damaged cap.
If the problem is detected twice in a row, the system will
turn on the Malfunction Indicator Light (MIL). Resolving
the problem will turn the MIL light off.
EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass
an inspection of your vehicle’s emissions control system.
Failure to pass could prevent vehicle registration.
For states, which have an I/M (Inspection and
Maintenance) requirement, this check verifies the
following: the MIL (Malfunction Indicator Light)
is functioning and is not on when the engine is running,
and that the OBD (On Board Diagnostic) system is ready
for testing.
Normally, the OBD system will be ready. The OBD
system maynotbe ready if your vehicle was recently
serviced, if you recently had a dead battery, or a battery
replacement. If the OBD system should be determined
not ready for the I/M test, your vehicle may fail the test.
366 MAINTAINING YOUR VEHICLE

vehicle serviced before going to the I/M station. The I/M
station can fail your vehicle because the MIL symbol is on
with the engine running.
REPLACEMENT PARTS
Use of genuine Moparparts for normal/scheduled
maintenance and repairs is highly recommended to in-
sure the designed performance. Damage or failures
caused by the use of non-Moparparts for maintenance
and repairs will not be covered by the manufacturer’s
warranty.
DEALER SERVICE
Your 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 manuals before attempting any procedure
yourself.NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
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.
368 MAINTAINING YOUR VEHICLE

MAINTENANCE PROCEDURES
The pages that follow contain therequiredmaintenance
services determined by the engineers who designed your
vehicle.
Besides the maintenance items for which there are fixed
maintenance intervals, there are other items that should
operate satisfactorily without periodic maintenance.
However, if a malfunction of these items does occur, it
could adversely affect the engine or vehicle performance.
These items should be inspected if a malfunction is
observed or suspected.
Engine Oil
Checking Oil Level
To assure proper lubrication of your vehicle’s engine, the
engine oil must be maintained at the correct level. The
best time to check the engine oil level is about 5 minutes
after a fully warmed up engine is shut off or before
starting the engine after it has sat overnight.Checking the oil while the vehicle is on level ground will
improve the accuracy of the oil level readings. Always
maintain the oil level within the SAFE zone on the
dipstick. Adding one quart of oil when the reading is at
the bottom of the SAFE zone will result in a reading at the
top of the safe zone on these engines.
MAINTAINING YOUR VEHICLE 369
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Spark Plugs
Spark plugs must fire properly to assure engine perfor-
mance and emission control. New plugs should be in-
stalled at the mileage specified in the appropriate main-
tenance chart. The entire set should be replaced if there is
any malfunction due to a faulty spark plug.
Refer to the “Vehicle Emission Control Information” label
in the engine compartment for spark plug information.
Catalytic Converter
The catalytic converter requires the use of unleaded fuel
only. Leaded gasoline will destroy the effectiveness of the
converter as an emission control device.
Under normal operating conditions, the catalytic con-
verter will not require maintenance. However, it is im-
portant to keep the engine properly tuned to assure
proper catalyst operation and prevent possible catalyst
damage.
CAUTION!
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.
MAINTAINING YOUR VEHICLE 373
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