
b. The MIL will not flash at all and will remain fully
illuminated until you turn off the ignition key or start
the engine. This means that your vehicle's OBD system
isreadyand you can proceed to the I/M station.
If your OBD system isnot ready,you should see your
authorized dealer or repair facility. If your vehicle was
recently serviced or had a battery failure or replacement,
you may need to do nothing more than drive your
vehicle as you normally would in order for your OBD
system to update. A recheck with the above test routine
may then indicate that the system is now ready.
Regardless of whether your vehicle's OBD system is
ready or not ready, if the MIL symbol is illuminated
during normal vehicle operation, you should have your
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 Mopartparts for normal/scheduled
maintenance and repairs is highly recommended to in-
sure the designed performance. Damage or failures
caused by the use of non-Mopartparts 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.
310 MAINTAINING YOUR VEHICLE

²Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean, also.
²Do not change the thermostat for summer or winter
operation. If replacement is ever necessary, install
ONLY the correct type thermostat. Other designs may
result in unsatisfactory coolant performance, poor gas
mileage, and increased emissions.
Hoses And Vacuum/Vapor Harnesses
Inspect surfaces of hoses and nylon tubing for evidence
of heat and mechanical damage. Hard or soft spots,
brittle rubber, cracking, tears, cuts, abrasions, and exces-
sive swelling indicate deterioration of the rubber.
Pay particular attention to those hoses nearest to high
heat sources such as the exhaust manifold. Inspect hose
routing to be sure hoses do not come in contact with any
heat source or moving component which may cause heat
damage or mechanical wear.Insure nylon tubing in these areas has not melted or
collapsed.
Inspect all hose connections such as clamps and cou-
plings to make sure they are secure and no leaks are
present.
Components should be replaced immediately if there is
any evidence of wear or damage that could cause failure.
Brake System
In order to assure brake system performance, all brake
system components should be inspected periodically.
Suggested service intervals can be found on the appro-
priate ªMaintenance Schedule.º Refer to Section 8 of this
manual.
MAINTAINING YOUR VEHICLE 329
7

WARNING!
Riding the brakes can lead to brake failure and
possibly an accident. Driving with your foot resting
or riding on the brake pedal can result in abnormally
high brake temperatures, excessive lining wear, and
possible brake damage. You wouldn't have your full
braking capacity in an emergency.
Brake And Power Steering Hoses
When the vehicle is serviced for scheduled maintenance,
inspect surface of hoses and nylon tubing for evidence of
heat and mechanical damage. Hard and brittle rubber,
cracking, tears, cuts, abrasion, and excessive swelling
indicate deterioration of the rubber. Particular attention
should be made to examining those hose surfaces nearest
to high heat sources, such as the exhaust manifold.Insure nylon tubing in these areas has not melted or
collapsed.
Inspect all hose connections such as clamps and cou-
plings to make sure they are secure and no leaks are
present.
NOTE:Often, fluid such as oil, power steering fluid,
and brake fluid are used during assembly plant opera-
tions to facilitate the assembly of hoses to couplings.
Therefore, oil wetness at the hose-coupling area is not
necessarily an indication of leakage. Actual dripping of
hot fluid when systems are under pressure (during
vehicle operation), should be noted before a hose is
replaced based on leakage.
NOTE:Inspection of brake hoses should be performed
whenever the brake system is serviced and at every
engine oil change. Inspect hydraulic brake hoses for
surface cracking, scuffing, or worn spots. If there is any
evidence of cracking, scuffing, or worn spots, the hose
330 MAINTAINING YOUR VEHICLE

EMISSION CONTROL SYSTEM MAINTENANCE
The ªScheduledº maintenance services, listed inbold
typemust be done at the times or mileages specified to
assure the continued proper functioning of the emission
control system. These, and all other maintenance services
included in this manual, should be done to provide best
vehicle performance and reliability. More frequent main-
tenance may be needed for vehicles in severe operating
conditions such as dusty areas and very short trip
driving.
Inspection and service also should be done any time a
malfunction is suspected.
NOTE:Maintenance, replacement, or repair of the emis-
sion control devices and systems on your vehicle may be
performed by any automotive repair establishment or
individual using any automotive part which has been
certified pursuant to U.S. EPA or, in the State of Califor-
nia, California Air Resources Board regulations.
MAINTENANCE SCHEDULES
There are two maintenance schedules that show the
requiredservice for your vehicle.
First is Schedule(B(. It is for vehicles that are operated
under the conditions that are listed below and at the
beginning of the schedule.
²Day or night temperatures are below 32ÉF (0ÉC)
²Stop and go driving
²Excessive engine idling
²Driving in dusty conditions
²Short trips of less than 10 miles (16.2 km)
²More than 50% of your driving is at sustained high
speeds during hot weather, above 90ÉF (32ÉC)
²Trailer towing
356 MAINTENANCE SCHEDULES
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Miles 108,000 111,000 114,000 117,000 120,000
(Kilometers) (180 000) (185 000) (190 000) (195 000) (200 000)
Drain and refill the automatic transmission fluid,
and replace filter.X
Drain and refill the transfer case fluid. X
Flush and replace the engine coolant/anti-freeze at 120
months, if not replaced at 102,000 miles (170 000 km).X
Inspection and service should also be performed anytime
a malfunction is observed or suspected. Retain all re-
ceipts.
LThis maintenance is recommended by the manufac-
turer to the owner, but is not required to maintain
emissions warranty.* This maintenance is not required if the belt was
previously replaced.
368 SCHEDULE ªBº
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![JEEP GRAND CHEROKEE 2008 WK / 3.G SRT Owners Manual Miles 108,000 114,000 120,000
(Kilometers) (180 000) (190 000) (200 000)
[Months] [108] [114] [120]
Change the engine oil and engine oil filter. X X X
Inspect the engine air cleaner filter, and replac JEEP GRAND CHEROKEE 2008 WK / 3.G SRT Owners Manual Miles 108,000 114,000 120,000
(Kilometers) (180 000) (190 000) (200 000)
[Months] [108] [114] [120]
Change the engine oil and engine oil filter. X X X
Inspect the engine air cleaner filter, and replac](/manual-img/16/7092/w960_7092-373.png)
Miles 108,000 114,000 120,000
(Kilometers) (180 000) (190 000) (200 000)
[Months] [108] [114] [120]
Change the engine oil and engine oil filter. X X X
Inspect the engine air cleaner filter, and replace if necessary.X
Inspect the PCV Valve, replace if necessary.LX
Inspect the drive belt, replace if necessary.* X
Inspect the brake linings. X
Flush and replace the engine coolant/anti-freeze if not done at
102,000 miles (170 000 km).X
Drain the transfer case and refill.X
Inspection and service should also be performed anytime
a malfunction is observed or suspected. Retain all re-
ceipts.
LThis maintenance is recommended by the manufac-
turer to the owner, but is not required to maintain
emissions warranty.* This maintenance is not required if the belt was
previously replaced.
SCHEDULE ªAº 373
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WARNING!
You can be badly injured working on or around a
motor vehicle. Do only that service work for which
you have the proper equipment. If you have any
doubt about your ability to perform a service job,
take your vehicle to a competent mechanic.
374 SCHEDULE ªAº
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Voltage............................. 181
Load Floor, Cargo....................... 166
Loading Vehicle
Tires ............................... 263
Locks................................. 26
Automatic Door........................ 27
Child Protection........................ 28
Door................................ 26
Power Door........................... 27
Lower Anchors and Tether for CHildren
(LATCH)............................60,61
Lubrication, Body....................... 321
Lumbar Support........................ 106
Maintenance Free Battery.................. 318
Maintenance Procedures................... 311
Maintenance Schedule.................... 356
Schedule ªAº......................... 369
Schedule ªBº......................... 359Maintenance Schedules.................... 356
Malfunction Indicator Light (Check Engine) . . 174,309
Manual, Service......................... 380
Memory Feature (Memory Seat)............. 114
Memory Seat........................... 114
Memory Seats and Radio.................. 114
Methanol............................. 279
Mini-Trip Computer...................... 186
Mirrors................................ 74
Automatic Dimming..................... 74
Electric Powered....................... 76
Electric Remote........................ 76
Exterior Folding........................ 75
Heated.............................. 77
Outside.............................. 75
Vanity............................... 77
Modifications/Alterations, Vehicle............. 8
Monitor, Tire Pressure System............... 275
Mopar Parts.........................310,379
INDEX 395
10