engine JEEP GRAND CHEROKEE 2004 WK / 3.G Service Manual

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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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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NOTE:If you tow a trailer frequently, especially in hilly
country or when the outdoor temperature is high, we
recommend that you change the transmission fluid at
30,000 mile (48 000 km) intervals.
CAUTION!
When pulling a heavy load or driving a fully loaded
vehicle use a premium unleaded fuel to help prevent
spark knock. If spark knock persists, lighten the
load. Otherwise, engine piston damage may result.
Other restrictions apply concerning trailer type, trailer
frontal area and tongue weight. Carefully review the
ªMinimum Vehicle Requirementsº chart in this section
before towing a trailer.
RECREATIONAL TOWING (BEHIND
MOTORHOME, ETC.)
CAUTION!
Internal damage to the transfer case will occur if a
front or rear wheel lift is used when recreational
towing.
NOTE:The transfer case must be in the N (Neutral)
position, and the transmission must be in the P (Park)
position for recreational towing.(Recreational towing is
not available on Quadra-Trac I equipped vehicles.)
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Shifting Into Neutral (N)
Use the following procedure to prepare your vehicle for
recreational towing.
CAUTION!
It is necessary to follow these steps to be certain that
the transfer case is fully in N (Neutral) before
recreational towing to prevent damage to internal
parts.
1. Depress brake pedal.
2. Shift transmission into N (Neutral).
3. Shift transfer case lever into N (Neutral).4. Start engine.
5. Shift transmission into D (Drive).
6. Release brake pedal and ensure that there is no vehicle
movement.
7. Shut the engine OFF and place the ignition key into
the unlocked OFF position.
8. Shift transmission into P (Park).
9. Apply parking brake.
10. Attach vehicle to the tow vehicle with tow bar.
11. Release parking brake.
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CAUTION!
Transmission damage may occur if the transmission
is shifted into P (Park) with the transfer case in N
(Neutral) and the engine running. With the transfer
case in N (Neutral) ensure that the engine is OFF
prior to shifting the transmission into P (Park) (refer
to steps7±8above).
Shifting Out Of Neutral (N)
Use the following procedure to prepare your vehicle for
normal usage.
1. Shift transmission into N (Neutral).
2. Shift transfer case lever to desired position.
3. Shift transmission into D (Drive).NOTE:When shifting out of transfer case N (Neutral),
turning the engine OFF may be required to avoid gear
clash.
WARNING!
You or others could be injured if you leave the
vehicle unattended with the transfer case in the N
(Neutral) position without first fully engaging the
parking brake. The transfer case N (Neutral) position
disengages both the front and rear driveshafts from
the powertrain and will allow the vehicle to move
regardless of the transmission position. The parking
brake should always be applied when the driver is
not in the vehicle.
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WHAT TO DO IN EMERGENCIES
CONTENTS
mHazard Warning Flashers.................236
mIf Your Engine Overheats.................237
mChanging A Flat Tire....................238
NJack And Lug Wrench Locations...........238
NSpare Tire Location....................239NTire Changing Procedure................242
mJump Starting Procedure..................246
mEmergency Tow Hooks Ð If Equipped........248
mTowing A Disabled Vehicle................248
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IF YOUR ENGINE OVERHEATS
In any of the following situations, you can reduce the
potential for overheating by taking the appropriate ac-
tion.
²On the highways Ð Slow down.
²In city traffic Ð While stopped, put transmission in N
(Neutral), but do not increase engine idle speed.
NOTE:There are steps that you can take to slow down
an impending overheat condition. If your air conditioner
is on, turn it off. The air conditioning system adds heat to
the engine cooling system and turning off the A/C
removes this heat. You can also turn the Temperature
Control to maximum heat, the Mode Control to floor, and
the Fan Control to High. This allows the heater core to act
as a supplement to the radiator and aids in removing heat
from the engine cooling system.
CAUTION!
Driving with a hot cooling system could damage
your vehicle. If the temperature gauge reads ªHº,
pull over and stop the vehicle. Idle the vehicle with
the air conditioner turned off until the pointer drops
back into the normal range. If the pointer remains on
the ªHº, and you hear continuous chimes, turn the
engine off immediately, and call for service.
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Tire Changing Procedure
Preparation
WARNING!
You can be injured or killed if you try to change a
wheel too close to moving traffic. Pull far enough off
the road to avoid being hit when operating the jack
or changing the wheel.
²Park on a firm, level surface well off the road to
provide ample work space. Put the transmission in P
(Park) and stop the engine. Set the parking brake
firmly and activate the hazard warning flasher.
Avoid jacking up the vehicle with occupants inside. If
the jack should fall, someone in the vehicle could be
hurt.
²Block the front and rear of the
diagonally opposite tire. For
example, if the right front tire
is being changed, block the
left rear wheel.
Instructions
1. Remove the spare tire from under the cargo floor, jack
and jack tools from under the left and right rear seat.
2. Loosen the lug nuts one-half turn counterclockwise.
3. Assemble the jack and jacking tools as shown. Connect
jack handle driver (A) to extension (B), then to the lug
wrench (C).
242 WHAT TO DO IN EMERGENCIES