2004 JEEP GRAND CHEROKEE tire type

Proper operation of four wheel drive vehicles depends on
tires of equal size, type, and circumference on each
wheel. Any difference will adversely affect shifting and
cause damage to the transfer case.
Because four wheel drive provides improved traction,
there is a tendency to exceed safe turning and stopping
speeds. Do not go faster than road conditions permit.
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.
Shift Positions
For additional information on the appropriate use of each
transfer case mode position, see the information below:
2WD
Rear Wheel Drive High Range Ð Normal street and
highway driving. Dry hard surfaced roads.
4 PART TIME
Part Time 4 Wheel Drive High Range Ð Locks the
transfer case inter-axle differential. Forces the front and
rear wheels to rotate at the same speed. Additional
traction for loose, slippery road surfaces only.
4 FULL TIME
Full Time 4 Wheel Drive High Range Ð Employs inter-
axle differential. Allows front and rear wheels to rotate at
different speeds. All roads surfaces.
188 STARTING AND OPERATING

5 km/h). Avoid attempting to engage or disengage 4LO
with the vehicle moving faster than 2 to 3 mph (3 to 5
km/h).
Quadra-Trac IITOperating
Instructions/Precautions Ð If Equipped
The Quadra-Trac IIttransfer case is fully automatic in the
normal driving 4 ALL TIME mode. The Quadra-Trac IIt
transfer case provides three mode positions Ð four wheel
drive high range, neutral, and four wheel drive low
range.
This transfer case is fully automatic in the 4 ALL TIME
mode. The 4 ALL TIME mode transmits torque to the rear
axle during normal driving, similar to a rear wheel drive
vehicle. When speed difference is increased between the
front and rear driveshafts the majority of engine torque
can be transmitted to the front driveshaft.
When additional traction is required, the 4LO position
can be used to lock the front and rear driveshafts togetherand force the front and rear wheels to rotate at the same
speed. The 4LO position is intended for loose, slippery
road surfaces only. Driving in the 4LO position on dry
hard surfaced roads may cause increased tire wear and
damage to driveline components.
When operating your vehicle in 4LO, the engine speed is
approximately three times that of the 4 ALL TIME
position at a given road speed. Take care not to overspeed
the engine and do not exceed 25 mph (40 km/h).
Proper operation of four wheel drive vehicles depends on
tires of equal size, type, and circumference on each
wheel. Any difference will adversely affect shifting and
cause damage to the transfer case.
Because four wheel drive provides improved traction,
there is a tendency to exceed safe turning and stopping
speeds. Do not go faster than road conditions permit.
STARTING AND OPERATING 191
5

ANTI-LOCK BRAKE SYSTEM
The Anti-Lock Brake System (ABS) is designed to aid the
driver in maintaining vehicle control under adverse
braking conditions. The system operates with a separate
computer to modulate hydraulic pressure to prevent
wheel lock-up and help avoid skidding on slippery
surfaces.
All vehicle wheels and tires must be the same size and
type and tires must be properly inflated to produce
accurate signals for the computer.
WARNING!
Significant over or under inflation of tires, or mixing
sizes of tires or wheels on the vehicle can lead to loss
of braking effectiveness.
The Anti-Lock Brake System conducts a low-speed self-
test at about 12 mph (20 km/h). If you have your foot
lightly on the brake while this test is occurring you may
feel slight pedal movement. The movement can be more
apparent on ice and snow. This is normal.
The Anti-Lock Brake System pump motor runs during
the self-test at 12 mph (20 km/h) and during an ABS stop.
The pump motor makes a low humming noise during
operation, which is normal.
WARNING!
Pumping of the Anti-Lock Brakes will diminish
their effectiveness and may lead to an accident.
Pumping makes the stopping distance longer. Just
press firmly on your brake pedal when you need to
slow down or stop.
STARTING AND OPERATING 197
5

Radial-Ply Tires
WARNING!
Combining radial ply tires with other types of tires
on your vehicle will cause your vehicle to handle
poorly. The instability could cause an accident. Al-
ways use radial tires in sets of four. Never combine
them with other types of tires.
Cuts and punctures in radial tires are repairable only in
the tread area because of sidewall flexing. Consult your
dealer for radial tire repairs.
Tire Spinning
When stuck in mud, sand, snow, or ice conditions, do not
spin your vehicle's wheels above 35 mph (55 km/h).
WARNING!
Fast spinning tires can be dangerous. Forces gener-
ated by excessive wheel speeds may cause tire dam-
age or failure. A tire could explode and injure
someone. Do not spin your vehicle's wheels faster
than 35 mph (55 km/h) when you are stuck. And
don't let anyone near a spinning wheel, no matter
what the speed.
214 STARTING AND OPERATING

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

TIRE CHAINS
Certain models have sufficient tire-to-body clearance to
allow use of tire chains.Install chains on rear tires only.
Follow these recommendations to guard against damage
and excessive tire and chain wear:
²Do not install tire chains or traction devices on ve-
hicles with larger than P225/75R16 size tires. These
tires are too large for sufficient body clearance with
chains or other traction devices.
²Use SAE class ªSº tire chains or traction devices only.
²Follow tire chain manufacturer's instructions for
mounting chains.
²Install chains snugly and tighten after 1/2 mile (1 km)
of driving.
²Do notexceed 35 mph (56 km/h), unless otherwise
specified by the chain manufacturer.
²Drive cautiously, avoiding large bumps, potholes and
extreme driving maneuvers.
TIRE ROTATION RECOMMENDATIONS
Tires on the front and rear axles of vehicles operate at
different loads and perform different steering, handling,
and braking functions. For these reasons, they wear at
unequal rates, and develop irregular wear patterns.
These effects can be reduced by timely rotation of tires.
The benefits of rotation are especially worthwhile with
aggressive tread designs such as those on On/Off Road
type tires. Rotation will increase tread life, help to main-
tain mud, snow, and wet traction levels, and contribute to
a smooth, quiet ride.
Follow the recommended tire rotation frequency for your
type of driving found in the ªMaintenance Schedulesº
Section of this manual. More frequent rotation is permis-
sible if desired. The reasons for any rapid or unusual wear
should be corrected prior to rotation being performed.
220 STARTING AND OPERATING

CHANGING A FLAT TIRE
Jack And Lug Wrench Locations
The three piece tool set, consisting of two snap-together
extensions that operate the jack and a wheel wrench that
also is used as a crank for the jack, is stored under the
right rear seat. The scissor-type jack is located under the
left rear seat.To remove the jack from its stowage position, turn the
wing nut counterclockwise to loosen the jack assembly,
and then remove it.
238 WHAT TO DO IN EMERGENCIES

dirty or rusty in appearance, the system should be
drained, flushed and refilled with fresh coolant.
Check the front of the radiator for any accumulation of
bugs, leaves, etc. Clean the radiator by gently spraying
water from a garden hose at the back of the core.
Check the engine cooling system hoses for condition and
tightness of connection. Inspect the entire system for
leaks. Any hoses that show cuts or severe abrasion must
be replaced.
Cooling System Ð Drain, Flush, And Refill
At the intervals shown in the appropriate ªMaintenance
Schedule,º the system should be drained, flushed, and
refilled.
If the solution is dirty and contains a considerable
amount of sediment, clean and flush with reliable cooling
system cleaner. Follow with a thorough rinsing to remove
all deposits and chemicals.
Engine Coolant Disposal
Used ethylene glycol-based engine coolant is a regulated
substance requiring proper disposal. Check with your
local authorities to determine the disposal rules for your
community. Do not store ethylene glycol-based engine
coolant in open containers or allow it to remain in
puddles on the ground. Prevent ingestion by animals and
children. If ingested by a child, contact a physician
immediately. Clean up any ground spills immediately.
Selection Of Coolant
Use only the manufacturer's recommended coolant, refer
to Recommended Fluids, Lubricants, and Genuine Parts
for correct coolant type.
270 MAINTAINING YOUR VEHICLE