2004 JEEP GRAND CHEROKEE service schedule

Brake Transmission Shift Interlock System (BTSI)
This vehicle is equipped with a brake transmission shift
interlock system (BTSI) that holds the gearshift lever in
the P (Park) position when the ignition switch is in an
unlocked position. To move the gear selector lever out of
the P (Park) position, the ignition switch must be turned
to the OFF, ON, or START position, the brake pedal and
the button on the front side of the shifter handle must be
depressed.
Electronically Controlled Five Speed Automatic
Transmission (4.7L Engine Only)
This electronically controlled transmission provides a
precise shift schedule. The transmission electronics are
self calibrating; therefore, the first few shifts on a new
vehicle may be somewhat abrupt. This is a normal
condition, and precision shifts will develop within a
couple hundred miles (kilometers).
Protect Mode - Electronically Controlled
Transmission (4.7L Engine Only)
This transmission is monitored electronically for abnor-
mal conditions. If an abnormal condition is detected, the
transmission's electronic controller will automatically
select direct gear (in the Drive position) or 2nd gear (in
the 2 or 1 position). This feature will allow the vehicle to
be driven to the dealer for service minimizing any
damage to the transmission. Some conditions that will
cause the transmission to use this alternate gear selection
are momentary and the transmission can be reset to the
normal shift program by performing the following:
²Stop the vehicle and shift into P (Park).
²Turn the ignition key to the OFF position and then
restart the engine.
²Shift into the desire shift range and resume driving.
180 STARTING AND OPERATING

TRAILER TOWING
In this section you will find information on limits to the
type of towing you can reasonably do with your vehicle.
And you will find safety tips. Before towing a trailer
carefully review this information to tow your load as
efficiently and safely as possible.
The factory-installed Class III and Class IV Trailer Tow
Packages include a frame mounted receptacle and the
above required equipment. They also include some nec-
essary provisions for connecting an aftermarket electric
brake controller. It is a light blue wire, identified with a
tag, located under the instrument panel behind the brake
pedal. Other equipment, such as trailer sway controls
and braking equipment, trailer equalizing (leveling)
equipment and low profile mirrors, may also be required
or strongly recommended.To maintain warranty coverage, follow the requirements
and recommendations in this manual concerning ve-
hicles used for trailer towing.
Perform maintenance services as prescribed in the appro-
priate ªMaintenance Schedule.º Refer to Section 8 of this
manual. When your vehicle is used for trailer towing,
never exceed the gross axle weight rating (GAWR) by the
addition of:
²The tongue weight of the trailer.
²The weight of any other type of cargo or equipment
put in or on your vehicle.
226 STARTING AND OPERATING

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 yourvehicle 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.
MAINTAINING YOUR VEHICLE 255
7

CAUTION!
Overfilling or underfilling the crankcase will cause
aeration or loss of oil pressure. This could damage
your engine.
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:
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 operation
²If 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 ªMaintenance Schedule B.º
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.
258 MAINTAINING YOUR VEHICLE

Drive Belts - Check Condition and Tension
At the mileages shown in the appropriate ªMaintenance
Schedule,º check all drive belts for condition and proper
tension. Improper belt tension can cause belt slippage
and failure.
Inspect the drive belt for evidence of cuts, cracks, or
glazing and replace them if there is any sign of damage
which could result in belt failure. If adjustment is re-
quired, adjust the belts according to the specifications
and procedures shown in the Service Manual.
Special tools are required to properly measure tension
and to restore belt tension to factory specifications. Also,
check belt routing to make sure there is no interference
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 the ªVehicle Emission Control Informa-
tionº 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.
MAINTAINING YOUR VEHICLE 261
7

apparent, and/or the system is not functioning as antici-
pated. Coordinate inspection efforts through a certified
ªDaimlerChrysler Dealership.º
WARNING!
Fluid level should be checked on a level surface with
the engine off to prevent injury from moving parts,
and to insure accurate fluid level reading. Do not
overfill. Use only the manufacturer's recommended
fluid.
If necessary, add fluid to restore to the proper indicated
level. With a clean cloth, wipe any spilled fluid from all
surfaces. Refer to Recommended Fluids, Lubricants, and
Genuine Parts for correct fluid type.
Driveline And Steering Component Lubrication
U-joints (cardan joints) are sealed and do not require
lubrication. Prop shafts, yokes, ball joints and other
driveline and steering components may be provided with
grease fittings for lubrication. Lubrication of these com-
ponents at the intervals specified in the appropriate
ªMaintenance Scheduleº in Section 8 is very important,
particularly if your vehicle is subjected to off-road or
other heavy-duty use. See your authorized dealer for
complete service information.
Body Lubrication
Locks and all body pivot points, including such items as
seat tracks, doors, tailgate and hood hinges, should be
lubricated periodically to assure quiet, easy operation
and to protect against rust and wear. Prior to the appli-
cation of any lubricant, the parts concerned should be
wiped clean to remove dust and grit; after lubricating
excess oil and grease should be removed. Particular
MAINTAINING YOUR VEHICLE 267
7

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 the hoses nearest to high heat
sources such as the exhaust manifold. Inspect hose rout-
ing to be sure hoses do not touch any heat source or
moving component that 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 couplings to make sure they are secure and no leaks
are present. Components should be replaced immedi-
ately if there is any evidence of degradation that could
cause failure.
Brake System
In order to assure brake system performance, all brake
system components should be inspected periodically.
Refer to the appropriate ªMaintenance Scheduleº 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,
274 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
296 MAINTENANCE SCHEDULES
8
M
A
I
N
T
E
N
A
N
C
E
S
C
H
E
D
U
L
E
S