2005 JEEP GRAND CHEROKEE service

WARNING!
•Remove the fuel cap (gas cap) slowly to prevent
fuel spray from the filler neck which may cause
injury.
•The volatility of some gasoline may cause a
buildup of pressure in the fuel tank that 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.
•Never have any smoking materials lit in or near
the vehicle when the fuel cap is removed or the
tank filled.
•Never add fuel to the vehicle when the engine is
running.
WARNING!
A fire may result if gasoline is pumped into a
portable container that is inside of a vehicle. You
could be burned. Always place gas containers on the
ground while filling.
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.
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 “Maintenance Schedule.” Refer to Section 8 of this
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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.
•On the highways — Slow down.
•In city traffic — 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 “H”,
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 “H”, and you hear continuous chimes, turn the
engine off immediately, and call for service.
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JACKING AND TIRE CHANGING
WARNING!
•Getting under a jacked-up vehicle is dangerous.
The vehicle could slip off the jack and fall on you.
You could be crushed. Never get any part of your
body under a vehicle that is on a jack. If you need
to get under a raised vehicle, take it to a service
center where it can be raised on a lift.
•The jack is designed to use as a tool for changing
tires only. The jack should not be used to lift the
vehicle for service purposes. The vehicle should
be jacked on a firm level surface only. Avoid ice or
slippery areas.
Jack Location
The scissor-type jack and tire changing tools are located
in a compartment behind the second row seat.
Jack Storage Location
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nuts until each nut has been tightened twice. Correct
wheel nut tightness is 130 N·m (95 ft. lbs). If in doubt
about the correct tightness, have them checked with a
torque wrench by your authorized dealer or at a service
station.
10. Lower the jack to it’s fully closed position.
WARNING!
A loose tire or jack, thrown forward in a collision or
hard stop could endanger the occupants of the ve-
hicle. Always stow the jack parts and the spare tire in
the places provided.
11. Secure the tire, jack, and tools in their proper loca-
tions.
NOTE:Tire should be stowed with the “beauty” side
up. Storing the tire upside down may result in scratchingor damage to the wheel face. Continue winching up the
tire until you hear the winch “ratchet” three times.
Double check to ensure the tire is snug against the
underbody of the vehicle. Damage to the winch cable
may result if the vehicle is driven with the tire loose.
12. Reinstall the rubber plug into the floor of the cargo
area.
JUMP STARTING PROCEDURE
NOTE:Check the test indicator on top of battery for
battery fluid level. If the indicator is clear, the level is low.
Add water to the proper level and reinstall the vent caps
before attempting to jump start the vehicle.
1. Wear eye protection and remove any metal jewelry
such as watch bands or bracelets that might make an
unintended electrical contact.
2. When boost is provided by a battery in another
vehicle, park that vehicle within booster cable reach but
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MAINTAINING YOUR VEHICLE
CONTENTS

3.7L Engine...........................310

4.7L Engine...........................311

5.7L Engine...........................312

Onboard Diagnostic System — OBD II........313
▫Loose Fuel Filler Cap Message............313

Emissions Inspection And Maintenance
Programs............................314

Replacement Parts......................315

Dealer Service.........................316
Maintenance Procedures..................316
▫Engine Oil..........................316
▫Drive Belts - Check Condition And Tension . . . 320
▫Spark Plugs.........................321
▫Catalytic Converter....................321
▫Ignition Cables.......................323
▫Crankcase Emission Control System........323
▫Fuel Filter..........................323
▫Air Cleaner Filter.....................323
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ONBOARD DIAGNOSTIC SYSTEM — OBD II
Your vehicle is equipped with a sophisticated onboard
diagnostic system called OBD II. This system monitors
the performance of the emissions, engine, and automatic
transmission control systems. When these systems are
operating properly, your vehicle will provide excellent
performance and fuel economy, as well as engine emis-
sions well within current government regulations.
If any of these systems require service, the OBD II system
will turn on the “Malfunction Indicator Light.” It will
also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be drivable and not
need towing, see your dealer for service as soon as
possible.CAUTION!
•Prolonged driving with the “Malfunction Indica-
tor Light” on could cause further damage to the
emission control system. It could also affect fuel
economy and driveability. The vehicle must be
serviced before any emissions tests can be per-
formed.
•If the “Malfunction Indicator Light” is flashing
while the engine is running, severe catalytic con-
verter damage and power loss will soon occur.
Immediate service is required.
Loose Fuel Filler Cap Message
After fuel is added, the vehicle diagnostic system can
determine if the fuel filler cap is loose, improperly
installed, or damaged. A loose fuel filler cap message will
be displayed in the instrument cluster. Tighten the gas
MAINTAINING YOUR VEHICLE 313
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cap until aclickingsound is heard. This is an indication
that the gas cap is properly tightened. Press the odometer
reset button to turn the message off. If the problem
persists, the message will appear the next time the
vehicle is started. This might indicate a damaged cap. If
the problem is detected twice in a row, the system will
turn on the Malfunction Indicator Light (MIL). Resolving
the problem will turn the MIL light off.
EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass
an inspection of your vehicle’s emissions control system.
Failure to pass could prevent vehicle registration.
For states which have an I/M (Inspection and
Maintenance) requirement, this check verifies the
following: the MIL (Malfunction Indicator Lamp)is functioning and is not on when the engine is running,
and that the OBD (On Board Diagnostic) system is ready
for testing.
Normally, the OBD system will be ready. The OBD
system maynotbe ready if your vehicle was recently
serviced, if you recently had a dead battery, or a battery
replacement. If the OBD system should be determined
not ready for the I/M test, your vehicle may fail the test.
Your vehicle has a simple ignition key actuated test
which you can use prior to going to the test station. To
check if your vehicle’s OBD system is ready, you must do
the following:
1. Insert your ignition key into the ignition switch.
2. Turn the ignition to the ON position, but do not crank
or start the engine.
3. If you crank or start the engine, you will have to start
this test over.
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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.
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