2006 JEEP GRAND CHEROKEE service schedule

4. As soon as you turn your key to the ON position, you
will see your MIL symbol come on as part of a normal
bulb check.
5. Approximately 15 seconds later, one of two things will
happen:
a. The MIL will flash for about 10 seconds and then
return to being fully illuminated until you turn off the
ignition key or start the engine. This means that your
vehicle’s OBD system isnot readyand you shouldnot
proceed to the I/M station.
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 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.
MAINTAINING YOUR VEHICLE 299
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Disposing of Used Engine Oil And Oil Filters
Care should be taken in disposing of used engine oil and
oil filters from your vehicle. Used oil and oil filters,
indiscriminately discarded, can present a problem to the
environment. Contact your dealer, service station, or
governmental agency for advice on how and where used
oil and oil filters can be safely discarded in your area.
Engine Oil Filter
The engine oil filter should be replaced at every engine
oil change.
Engine Oil Filter Selection
The manufacturer’s engines have a full-flow type oil
filter. Use a filter of this type for replacement. The quality
of replacement filters varies considerably. Only high
quality filters should be used to assure most efficient
service. Mopar Engine Oil Filters are a high quality oil
filter and are recommended.
Drive Belts — Check Condition and Tensioner
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 on the appropriate “Mainte-
nance 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 interfer-
ence between the belts and other engine components.
304 MAINTAINING YOUR VEHICLE

Spark Plugs
Spark plugs must fire properly to assure engine perfor-
mance and emission control. New plugs should be in-
stalled at the specified mileage. The entire set should be
replaced if there is any malfunction due to a faulty spark
plug. Malfunctioning spark plugs can damage the cata-
lytic converter. For proper type of replacement spark
plugs, refer to the “Vehicle Emission Control Informa-
tion” label in the engine compartment.
Engine Air Cleaner Filter
Under normal driving conditions, replace the air filter at
the intervals shown on “Maintenance Schedule A.” If,
however, you drive the vehicle frequently under dusty or
severe conditions, the filter element should be inspected
periodically and replaced if necessary at the intervals
shown on “Maintenance Schedule B.”
WARNING!
The air cleaner can provide a measure of protection
in the case of engine backfire. Do not remove the air
cleaner unless such removal is necessary for repair or
maintenance. Make sure that no one is near the
engine compartment before starting the vehicle with
the air cleaner removed. Failure to do so can result in
serious personal injury.
Fuel Filter
A plugged fuel filter can cause stalling, limit the speed at
which a vehicle can be driven or cause hard starting.
Should an excessive amount of dirt accumulate in the
fuel tank, filter replacement may be necessary. See your
local dealer for service.
MAINTAINING YOUR VEHICLE 305
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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 “Maintenance Schedule.” Refer to Section 8 of this
manual.
MAINTAINING YOUR VEHICLE 319
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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
320 MAINTAINING YOUR VEHICLE

EMISSION CONTROL SYSTEM MAINTENANCE
The “Scheduled” 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 ScheduleB. It is for vehicles that are operated
under the conditions that are listed below and at the
beginning of the schedule.
•Day or night temperatures are below 32°F (0°C)
•Stop and go driving
•Excessive 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
346 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)
Change the engine oil and engine oil filter, if not replaced
at 3 months.X X XXX
Inspect the engine air cleaner filter, replace if necessary.X
Inspect the PCV Valve, replace if necessary.X
Inspect the drive belt, replace if necessary.* X
Inspect the brake linings. X X
Drain and refill the front and rear axle fluid. X
Drain and refill the automatic transmission fluid, and re-
place 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 receipts.
This 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 “B” 357
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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.X
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.
This 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.
362 SCHEDULE “A”
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