2008 JEEP GRAND CHEROKEE service schedule

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.
WARNING!
You can be badly injured working on or around a
motor vehicle. Do only that 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.
MAINTAINING YOUR VEHICLE 393
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Drive Belts Ð Check Condition and Tension
Belt tension is controlled by means of an automatic
tensioner. No belt tension adjustments are required.
However, belt and belt tensioner condition should be
inspected at the specified intervals, and replaced if re-
quired. See your authorized dealer for service.
At the mileage indicated in the maintenance schedule, all
belts and tensioner should be checked for condition.
Improper belt tension can cause belt slippage and failure.
Belts should be inspected for evidence of cuts, cracks,
glazing, or frayed cords and replaced if there is indication
of damage which could result in belt failure. Low gen-
erator belt tension can cause battery failure.
Also, check belt routing to make sure there is no inter-
ference between the belts and other engine components.
Spark Plugs
Spark plugs must fire properly to assure engine perfor-
mance and emission control. New spark plugs should be
installed at the specified mileage. The entire set should be
replaced if there is any malfunction due to a faulty spark
plug. Refer to ªFluids, Lubricants, and Genuine Partsº in
this section for spark plug information.
Spark Plug Wires
The spark plug wires should be kept clean and properly
connected. Terminals should be fully seated. Cracked,
damaged, or faulty wires should be replaced.
Engine Air Cleaner Filter
Refer to the Maintenance Schedule for recommended
Engine Air Cleaner Filter change intervals.
398 MAINTAINING YOUR VEHICLE

You are urged to use only the manufactures-specified
tubes, connections and clamps, or their equivalent in
material and specification, in any fuel system servicing.
Brake System
In order to assure brake system performance, all brake
system components should be inspected periodically.
Refer to the Maintenance Schedule in Section 8 for
suggested service intervals.
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 System Hoses
When servicing the vehicle for scheduled maintenance,
inspect surface of hoses for evidence of heat and me-
chanical damage. Hard and brittle rubber, cracking, tears,
cuts, abrasion, and excessive swelling suggest deteriora-
tion of the rubber. Particular attention should be made to
examining those hose surfaces nearest to high heat
sources, such as the exhaust manifold.
Inspect all hose clamps and couplings to make sure they
are secure and no leaks are present.
NOTE:Often fluids such as oil, power steering fluid,
and brake fluid are used during assembly plant opera-
tions to ease the assembly of hoses to couplings. There-
fore, oil wetness at the hose-coupling area is not neces-
sarily an indication of leakage. Actual dripping of hot
fluid when systems are under pressure (during vehicle
operation) should be noted before hose is replaced based
on leakage.
MAINTAINING YOUR VEHICLE 413
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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 SCHEDULE Ð GASOLINE
ENGINES
The oil change indicator system will remind you that it is
time to take your vehicle in for scheduled maintenance.
On Electronic Vehicle Information Center (EVIC)
equipped vehicles, ªOil Change Requiredº will be dis-
played in the EVIC and a single chime will sound,
indicating that an oil change is necessary.
Based on engine operation condition the oil change
indicator message will illuminate, this means that service
is required for your vehicle. Have your vehicle serviced
as soon as possible, within the next 500 miles (805 km).
NOTE:
²The oil change indicator message will not monitor the
time since the last oil change. Change your vehicles oil
if it has been 6 months since your last oil change even
if the oil change indicator message is NOT illumi-
nated.
444 MAINTENANCE SCHEDULES
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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 knowledge and the right equipment. If
you have any doubt about your ability to perform a
service job, take your vehicle to a competent
mechanic.
MAINTENANCE SCHEDULES Ð DIESEL ENGINE
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.
²Extensive 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.
²Taxi, police, or delivery service (commercial service).
MAINTENANCE SCHEDULES 449
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Schedule ªBº Ð Diesel Engine
Follow schedule ªBº if you usually operate your vehicle
under one or more of the following conditions.
²Day or night temperatures are below 32ÉF (0ÉC).
²Stop and go driving.
²Extensive 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.
²Taxi, police, or delivery service (commercial service).
²Off-road or desert driving.
452 SCHEDULE ªBº Ð DIESEL ENGINE
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LApplies only if vehicle is used for frequent trailer
towing, or fleet/commercial service.
² The replacement of such component is requested when
there is superficial wear, bearing clearance, or evident
grease leak.Inspection and service should be performed anytime a
malfunction is observed or suspected. Retain all receipts.
456 SCHEDULE ªBº Ð DIESEL ENGINE
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Miles 62,500 75,000 87,500 100,000
(Kilometers) (100 000) (120 000) (140 000) (160 000)
Change the engine oil and engine oil filter. X X X X
Rotate the tires. X X X X
Check spare tire for proper pressure and correct stowage. X X X X
Inspect the engine air filter element. Replace as neces-
sary.XX
Replace the engine air filter element.XX
Replace the fuel filter/water separator unit. X X
Flush and replace the engine coolant/anti-freeze. X
Replace the engine accessory drive belt. X
Inspect the brake linings. X X
Drain the transfer case and refill. X X
Inspection and service should be performed anytime a
malfunction is observed or suspected. Retain all receipts.LThe replacement of such component is requested
when there is superficial wear, bearing clearance, or
evident grease leak.
458 SCHEDULE ªAº Ð DIESEL ENGINE
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