2007 JEEP GRAND CHEROKEE fuel

MAINTAINING YOUR VEHICLE
CONTENTS

Engine Compartment – 3.7L...............354

Engine Compartment – 4.7L...............355

Engine Compartment – 5.7L...............356

Engine Compartment – 3.0L Diesel..........357

Onboard Diagnostic System — OBD II........358
▫Loose Fuel Filler Cap Message............358

Emissions Inspection And Maintenance
Programs............................359

Replacement Parts......................361
Dealer Service.........................361

Maintenance Procedures..................362
▫Engine Oil..........................362
▫Drive Belts — Check Condition And Tension . . 366
▫Spark Plugs.........................367
▫Spark Plug Wires.....................367
▫Engine Air Cleaner Filter................367
▫Catalytic Converter....................368
▫Crankcase Emission Control System........369
7

▫Maintenance-Free Battery................370
▫Air Conditioner Maintenance.............371
▫Power Steering Fluid Check..............372
▫Body Lubrication.....................374
▫Windshield Wiper Blades................374
▫Windshield Washers — Front And Rear.....374
▫Exhaust System......................375
▫Cooling System.......................376
▫Hoses And Vacuum/Vapor Harnesses.......381
▫Fuel System Connections................382
▫Brake System........................382
▫Front/Rear Axle Fluid..................385
▫Transfer Case........................385▫Automatic Transmission................386
▫Appearance Care And Protection From
Corrosion...........................389

Fuse Panel...........................393
▫Interior Fuses........................393
▫Underhood Fuses (Power Distribution
Center)............................396
▫Underhood Fuses (Integrated Power
Module)............................399

Vehicle Storage........................400

Replacement Bulbs......................401

Bulb Replacement......................402
▫Head Light..........................402
▫Front Turn Signal.....................403
352 MAINTAINING YOUR VEHICLE

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.” 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 dealer for service as soon as
possible.CAUTION!
•Prolonged driving with the “Malfunction Indica-
tor Light” on could cause further damage to the
emission control system. It could also affect fuel
economy and driveability. The vehicle must be
serviced before any emissions tests can be per-
formed.
•If the “Malfunction Indicator Light” is flashing
while the engine is running, severe catalytic con-
verter 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 loose, improperly
installed, or damaged. A “CHECK GASCAP” message
will be displayed in the EVIC (Refer to Section 4 of this
358 MAINTAINING YOUR VEHICLE

manual). Tighten the gas cap until aclickingsound is
heard. This is an indication that the gas cap is properly
tightened.
This message may be temporarily overridden by pressing
either the C/T, STEP, or MENU buttons. However, after
one minute of no customer interaction, the EVIC will
display again the “CHECK GASCAP” message. The
message will remain displayed until the vehicle diagnos-
tic system can retest the fuel system. The test will
perform the next time the vehicle is started, if the vehicle
was keyed off above 40°F (4°C) outside temperature and
the following vehicle start is above 40°F (4°C) outside
temperature. It may be possible to have a message that
will not clear due to the test being disabled due to low
outside temperatures. If the test is performed and the
problem is gone, the message will disappear.
If the problem persists, the message will appear the next
time the vehicle is started. This might indicate a damagedcap. 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. See
your authorized dealer for service.
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 Lamp)
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
MAINTAINING YOUR VEHICLE 359
7

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 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 tocheck the engine oil level is about 5 minutes after a fully
warmed 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. Maintain
the oil level in the SAFE level range. Adding 1 U.S. Quart
(0.95L) of oil when the level is at the bottom of the SAFE
range will result in the level being at the top of the SAFE
range.
CAUTION!
Overfilling or underfilling the crankcase will cause
aeration or loss of oil pressure. This could damage
your engine.
362 MAINTAINING YOUR VEHICLE

Change Engine Oil
Road conditions as well as your kind of driving affect the
interval at which your oil should be changed. Check the
following to determine if any apply to you:
•Day or night temperatures are below 32°F (0°C)
•Stop and go driving
•Extensive engine idling
•Driving in dusty conditions
•Short trips of less than 10 miles (16.2 km)
•More than 50% of your driving is at sustained high
speeds during hot weather, above 90°F (32°C)
•Trailer towing
•Taxi, Police, or delivery service (Commercial Service)
•Off road or desert operation
•If equipped for and operating with E-85 (ethanol)
fuel.
IfANYof these apply to you, then change your engine oil
every 3,000 miles (5 000 km) or 3 months, whichever
comes first, and follow the maintenance recommenda-
tions in “Maintenance Schedule B.”
If none of these apply to you, then change your engine oil
every 6,000 miles (10 000 km) or 6 months, whichever
comes first.
NOTE:Under no circumstances should oil change in-
tervals exceed 6,000 miles (10 000 km) or 6 months
whichever comes first.
Engine Oil Selection — Gasoline Engines
For best performance and maximum protection for all
engines under all types of operating conditions, the
manufacturer recommends engine oils that are API Cer-
tified and meet the requirements of DaimlerChrysler
MAINTAINING YOUR VEHICLE 363
7

Material Standard MS-6395. Use Moparor an equiva-
lent oil meeting the specification MS-6395.
Engine Oil Selection - Diesel Engines
For best performance and maximum protection for all
engines under all types of operating conditions, the
manufacturer recommends engine oils that are API Cer-
tified and meet the requirements of DaimlerChrysler
Material Standard MS-11106 or Mercedes Benz MB 229.51
and ACEA C3 qualified engine oils
American Petroleum Institute (API) Engine Oil
Identification Symbol
This symbol means that the oil has
been certified by the American
Petroleum Institute (API). The
manufacturer only recommends
API Certified engine oils that
meet the requirements of
DaimlerChrysler Material Stan-
dard MS-6395. Use Moparor an
equivalent oil meeting the specifi-
cation MS-6395.
Engine Oil Viscosity (3.7L/4.7L/5.7L Engines)
SAE 5W-20 engine oil is recommended for all operating
temperatures. This engine oil improves low tempera-
ture starting and vehicle fuel economy. Your engine oil
filler cap also shows the recommended engine oil
viscosity for your vehicle.
364 MAINTAINING YOUR VEHICLE

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.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
368 MAINTAINING YOUR VEHICLE