2004 JEEP GRAND CHEROKEE service

NOTE:Even if the transmission can be reset, it is
recommend that you see your dealer at your earliest
possible convenience. Your dealer has the proper diag-
nostic equipment to determine if the problem could
recur. If the transmission is cannot be reset, dealer service
is required.
Gear Ranges
DO NOT race the engine when shifting from P (Park) or
N (Neutral) position into another gear range.
PÐPark
Supplements the parking brake by locking the transmis-
sion. The engine can be started in this range. Never use P
(Park) while the vehicle is in motion. Apply the parking
brake when leaving the vehicle in this range. Always
apply the parking brake first, then place the selector in P
(Park) position.
WARNING!
Unintended movement of a vehicle could injure
those in and near the vehicle. As with all vehicles,
you should never exit a vehicle while the engine is
running. Before exiting a vehicle, you should always
shift the vehicle into P (Park), remove the key from
the ignition, and apply the parking brake. Once the
key is removed from the ignition, the transmission
shift lever is locked in the P (Park) position, securing
the vehicle against unwanted movement. Further-
more, you should never leave children unattended
inside a vehicle.
The following indicators should be used to ensure that
you have engaged the transmission shift lever into the P
(Park) position:
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After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road it is
always a good idea to check for damage. That way you
can get any problems taken care of right away and have
your vehicle ready when you need it.
²Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
²Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
²Check for accumulations of plants or brush. These
things could be a fire hazard. They might hide damage
to fuel lines, brake hoses, axle pinion seals, and
propeller shafts.
²After extended operation in mud, sand, water, or
similar dirty conditions, have brake rotors, wheels,
brake linings, and axle yokes inspected and cleaned as
soon as possible.
WARNING!
Abrasive material in any part of the brakes may
cause excessive wear or unpredictable braking. You
might not have full braking power when you need it
to prevent an accident. If you have been operating
your vehicle in dirty conditions, get your brakes
checked and cleaned as necessary.
²If you experience unusual vibration after driving in
mud, slush or similar conditions, check the wheels for
impacted material. Impacted material can cause a
wheel imbalance and freeing the wheels of it will
correct the situation.
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EXAMPLE:
Service Description:
95= Load Index
ÐA numerical code associated with the maximum load a tire can carry.
H= Speed Symbol
ÐA symbol indicating the range of speeds at which a tire can carry a load corresponding
to its load index under certain operating conditions.
ÐThe maximum speed corresponding to the Speed Symbol should only be achieved un-
der specified operating conditions. (ie. tire pressure, vehicle loading, road conditions and
posted speed limits).
Load Identification:
(....blank....(= Absence of any text on sidewall of the tire indicates a Standard Load (SL) Tire
Extra Load (XL)= Extra Load (or Reinforced) Tire
Light Load= Light Load Tire
C,D,E= Load range associated with the maximum load a tire can carry at a specified pressure
Maximum LoadÐ Maximum Load indicates the maximum load this tire is designed to carry.
Maximum PressureÐ
Maximum Pressure indicates the maximum permissible cold tire inflation pressure for this tire.
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NOTE:The Tire Pressure Monitor system must be
retrained following a tire rotation. See your authorized
dealer for service.
The suggested rotation method is the ªforward-crossº
shown in the following diagram.FUEL REQUIREMENTS
Your engine is designed to meet all emis-
sions regulations and provide excellent
fuel economy and performance when us-
ing high quality unleaded gasoline having
an octane rating of 87. The use of premium
gasoline is not recommended. The use of
premium gasoline will provide no benefit over high
quality regular gasoline, and in some circumstances may
result in poorer performance.
NOTE: 4.7L HO Engines (If Equipped): High quality
premium unleaded gasoline with an octane rating of 91
is recommended but not required.
Light spark knock at low engine speeds is not harmful to
your engine. However, continued heavy spark knock at
high speeds can cause damage and immediate service is
required. Engine damage resulting from operation with a
heavy spark knock may not be covered by the new
vehicle warranty.
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Poor quality gasoline can cause problems such as hard
starting, stalling and hesitations. If you experience these
symptoms, try another brand of gasoline before consid-
ering service for the vehicle.
Over 40 auto manufacturer's world wide have issued and
endorsed consistent gasoline specifications (the World-
wide Fuel Charter, WWFC) to define fuel properties
necessary to deliver enhanced emissions, performance,
and durability for your vehicle. The manufacturer recom-
mends the use of gasoline that meets the WWFC speci-
fications if they are available.
Reformulated Gasoline
Many areas of the country require the use of cleaner
burning gasoline referred to as Reformulated Gasoline.
Reformulated gasoline contains oxygenates, and is spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.The manufacturer strongly supports the use of reformu-
lated gasoline. Properly blended reformulated gasoline
will provide excellent performance and durability for the
engine and fuel system components.
Gasoline/Oxygenate Blends
Some fuel suppliers blend unleaded gasoline with oxy-
genates such as 10% ethanol, MTBE, and ETBE. Oxygen-
ates are required in some areas of the country during the
winter months to reduce carbon monoxide emissions.
Fuels blended with these oxygenates may be used in
your vehicle.
CAUTION!
DO NOT use gasoline containing METHANOL.
Gasoline containing methanol may damage critical
fuel system components.
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MMT In Gasoline
MMT is a manganese containing metallic additive that is
blended into some gasoline to increase octane. Gasoline
blended with MMT provides no performance advantage
beyond gasoline of the same octane number without
MMT. Gasoline blended with MMT reduces spark plug
life and reduces emission system performance in some
vehicles. The manufacturer recommends that gasoline
without MMT be used in your vehicle. The MMT content
of gasoline may not be indicated on the gasoline pump,
therefore, you should ask your gasoline retailer whether
or not his/her gasoline contains MMT.
It is even more important to look for gasoline without
MMT in Canada because MMT can be used at levels
higher than allowed in the United States. MMT is pro-
hibited in Federal and California reformulated gasoline.
Sulfur In Gasoline
If you live in the northeast United States, your vehicle
may have been designed to meet California low emission
standards with clean burning, low sulfur, California
gasoline. Gasoline sold outside of California is permitted
to have higher sulfur levels which may affect the perfor-
mance of the vehicle's catalytic converter. This may cause
the ªMalfunction Indicator Lightº to illuminate.
Illumination of this light while operating on high sulfur
gasoline does not necessarily mean your emission control
system is malfunctioning. The manufacturer recom-
mends that you try a different brand of unleaded gaso-
line having lower sulfur to determine if the problem is
fuel related prior to returning your vehicle to an autho-
rized dealer for service.
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CAUTION!
If the ªMalfunction Indicator Lightº is flashing,
immediate service is required. See ªOnboard Diag-
nostic Systemº in Section 7 of this manual.
Materials Added To Fuel
All gasoline sold in the United States is required to
contain effective detergent additives. Use of additional
detergents or other additives is not needed under normal
conditions.
FUEL TANK FILLER CAP (GAS CAP)
WARNING!
To avoid fuel spillage and overfilling, do not ªtop
offº the fuel tank after filling.
The gas cap is located behind the fuel filler door, on the
left side of the vehicle. If the gas cap is lost or damaged,
be sure the replacement cap has been designed for use
with this vehicle. When the gas cap is removed for
refueling, it can be placed in the fuel filler door while
filling the fuel tank.
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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.
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