2004 JEEP GRAND CHEROKEE pressure

Alignment and Balance
The suspension components of your vehicle should be
inspected and aligned when needed, to obtain maximum
tire tread life.
Poor suspension alignment may result in:
²reduced tread life;
²uneven tire wear, such as feathering and one-sided
wear;
²vehicle pull to the right or to the left.
Tires may also cause the vehicle to pull left or right.
Alignment will not correct this problem. See your dealer
for proper diagnosis of the problem.
Improper alignment will not normally cause vehicle
vibration, which may be a result of tire and wheel
out-of-balance. Proper balancing will reduce vibration
and avoid tire cupping and spotty wear.
TIRE PRESSURE MONITOR SYSTEM Ð IF
EQUIPPED
The Tire Pressure Monitor System (TPM) monitors the
pressure in all 4 road tires and the full size spare (5 Tire
TPM System Only). The TPM system uses wireless
technology to monitor tire pressure levels. Sensors,
mounted to each wheel as part of the valve stem, transmit
tire pressure readings to a receiver located in the over-
head console. The tire pressure status is shown in the
Electronic Vehicle Information Center (EVIC) display.
Refer to ªOverhead Consoleº in Section 3 for more
information. The TPM system functions even when the
EVIC is not set on the tire pressure display screen.
The TPM system informs you of a low or high tire
pressure condition. If this occurs, correct your tire infla-
tion pressure as soon as possible, and inspect all of your
tires. Be sure to use a high quality gauge when adjusting
pressure. The TPM system is designed to monitor your
tire pressure but will not function as a tire pressure
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gauge. There will be a delay between the instant you
adjust the air pressure in a tire and when the system
updates the display. The TPM system is not intended to
provide you with notification of rapid air loss.
The following chart indicates the TPM system pressure
levels. A threshold is the level at which the TPM system
provides you with an indication.
High Pressure Threshold 45 psi (310 kPa )
Placard Pressure (Cold) 33 psi (227 kPa)
Low Pressure Threshold 25 psi (172 kPa)
NOTE: A TPM system does not replace normal tire
maintenance.
CAUTION!
The TPM system has been optimized for the original
equipment tires and wheels. TPM system pressures
have been established for the tire size equipped on
your vehicle. Undesirable operation or sensor dam-
age may result when using replacement equipment
that is not of the same size, type, and/or style.
Aftermarket wheels can cause sensor damage. Do
not use tire sealant or balance beads if your vehicle
is equipped with TPM system as damage to the
sensors may result.
Tire Pressure Monitor System Tire/Wheel
Rotation and Sensor Replacement Ð If Equipped
With the 5 Tire TPM System, if a road tire and wheel is
replaced by the spare, the TPM system will detect the
swap automatically (after the ignition has been cycled)
218 STARTING AND OPERATING

and display SPARE SWAP DETECTED along with a
chime. This could take up to 10 minutes with vehicle
speed above 25 mph (40 km/h).
With the 4 Tire TPM System, if a road tire and wheel is
replaced by the spare, the TPM system will display TIRE
SENSOR BAD/MISSING. This is due to the spare tire not
being equipped with a tire pressure sensor. Once the road
tire is repaired and/or installed back on the vehicle with
the proper tire pressure the message will be removed.
This could take up to 10 minutes with vehicle speed
above 25 mph (40 km/h).
The tire pressure sensorsmustbe retrained following a
wheel rotation or sensor replacement. Refer to ªEVIC Ð
Retrain Tire Sensorsº in Section 3 for more information. It
is necessary to program the EVIC with the new sensor(s)
or the new position of each sensor as it is rotated to a
different corner of the vehicle.If a wheel rotation is not followed by the retrain proce-
dure, the system will not properly inform you of the
correct vehicle location of a low or high tire pressure.
General Information
This device complies with part 15 of the FCC rules and
RSS 210 of Industry Canada. Operation is subject to the
following conditions:
²This device may not cause harmful interference.
²This device must accept any interference received,
including interference that may cause undesired op-
eration.
The tire pressure sensors are covered under one of the
following licenses:
United States.....................KR5S120123
Canada........................2671-S120123
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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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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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seatback or completely removed from the vehicle. It can
also be kneeled down upon and used as ground cover
to prevent clothing from getting soiled.
3. Remove the nut and tire.To Replace the Spare Tire
1. Place the tire into the rear compartment with the
wheel facing upward:
a. Replace the hold-down nut.
b. Reinstall the cover by inserting the hinges through
the carpet into the brackets at about a 30 degree angle
and lower into position. Press down to lock the cover
in position.
2. Your vehicle is equipped with either a temporary-use
spare tire or a conventional spare tire. Maintain the
temporary-use spare tire pressure at 60 psi (420 kPa), and
the conventional spare at 33 psi (228 kPa).
240 WHAT TO DO IN EMERGENCIES

WARNING!
Temporary-use spare tires are for emergency use
only. With these tires, do not drive more than 50
miles (80 km) or exceed 50 mph (80 km/h).
Temporary-use spare tires have a total tread life of
3,000 miles (4 800 km). Be sure to follow the warn-
ings which apply to your spare. Failure to do so
could result in spare tire failure and loss of vehicle
control.
Compact Spare Tire
²
Your vehicle is equipped with either a temporary-use
spare tire or a conventional spare tire. Maintain the
temporary-use spare tire pressure at 60 psi (420 kPa),
and the conventional spare at 33 psi (228 kPa).
²Temporary use spare tires are for emergency use only,
and are not intended for driving more than 50 miles
(80 km) or exceeding 50 mph (80 km/h).
²Never drive your vehicle with more than one compact
spare installed at any time.
²If your vehicle is equipped with Selec-Trac, avoid
using four-wheel drive when a compact spare is
installed. You should use 2WD only unless 4WD is
necessary. 4 FULL TIME should be used if 4WD is
required.
WHAT TO DO IN EMERGENCIES 241
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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