JEEP GRAND CHEROKEE 2004 WK / 3.G Owners Manual

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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CAUTION!
Damage to the fuel system or emission control
system could result from using an improper fuel
tank filler cap (gas cap). A poorly fitting cap could let
impurities into the fuel system.
WARNING!
²Remove the fuel cap slowly to prevent fuel spray
from the filler neck which may cause injury.
²The volatility of some gasoline may cause a
buildup of pressure in the fuel tank which may
increase while you drive. This pressure can result
in a spray of gasoline and/or vapors when the cap
is removed from a hot vehicle. Removing the cap
slowly allows the pressure to vent and prevents
fuel spray.
²Never add fuel when the engine is running.
²Never have any smoking materials lit in or near
the vehicle when the fuel cap is removed or the
tank filled.
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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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WARNING!
Improper towing can lead to an injury accident.
Follow these guidelines to make your trailer towing
as safe as possible:
²Be sure a trailer is loaded heavier in front, about 10%
to 15% of gross trailer weight. Loads balanced over the
wheels or heavier in the rear cause the trailer to sway
severelyside to side which will cause loss of control of
the vehicle and trailer. Failure to load trailers heavier
in front is the cause of many trailer related accidents.
²Donotinterconnect the hydraulic brake system of
your vehicle with that of the trailer. This could cause
inadequate braking and possible personal injury.
²Trailer brakes are required for trailers in excess of
2,000 lbs (907 kg).
²Donotconnect a trailer lighting system directly to the
lighting system of your vehicle. Use an approved
trailer wiring harness. Failure to do so could damage
the vehicle electrical system and/or result in personal
injury.
²When hauling cargo or towing a trailer,do notover-
load your vehicle or trailer. Overloading can cause a
loss of control, poor performance or damage to brakes,
axle, engine, transmission, steering, suspension, body
structure or tires.
²Make certain that the load is secured in the trailer and
will not shift during travel.
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²It is recommended thatanyhitches installed on your
vehicle be factory installed, or installed by a dealer
using factory approved parts. Factory approved parts
are specifically engineered with your vehicle's perfor-
mance in mind, including the possibility that it will be
involved in an accident. Other hitches may not have
been so engineered. Vehicle performance, including
vehicle damage in an accident situation, may therefore
be different.
²If trailer towing is required and your vehicle is not
equipped with a trailer tow package, the Mopart
accessory towing harnesses are the only approved
method to provide for trailer lights. These harnesses
are designed to provide current to the trailer lights but
bypass the module designed to monitor tail lights.
Refer to the package instructions for details.
Trailer and Tongue Weight
Gross Trailer Weight (GTW) means the weight of the
trailer plus the weight of all cargo, consumables and
equipment loaded on the trailer when in actual underway
towing condition. The best way to measure GTW is to put
your fully loaded trailer on a vehicle scale. The entire
weight of the trailer must be supported by the scale.
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Always load a trailer with 60% of the cargo weight in the
front of the trailer. This places approximately 10% to 15%
of the GTW on the tow hitch of your vehicle. This portion
of the GTW becomes the tongue weight.
Trailer sway control and equalizing hitch are required for
tongue weights above 350 lbs (159 kg)., i.e., trailer
weights heavier than 3,500 lbs (1 587 kg).
Cooling System TipsÐTrailer Towing
To reduce potential for engine and transmission over-
heating in high ambient conditions, take the following
actions:
²City Traffic
When stopped, put transmission in N (Neutral) and
increase engine idle speed.
²Highway Driving
Reduce speed.
²Air Conditioning
Turn off temporarily.
To reduce the potential for transmission overheating,
turn the ªOverdriveº off when pulling any trailer or shift
the transmission to Drive position 2 on more severe
grades. Move the shift lever to the next lower position to
eliminate excessive transmission shifting. This action will
also reduce the possibility of transmission overheating
and provide better engine braking.
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Minimum Vehicle Requirements for Trailer Towing
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