2005 JEEP GRAND CHEROKEE tire type

and Traction Control, provides resistance to any wheel
that is slipping to allow additional torque transfer to
wheels with traction.
NOTE:The Quadra-Trac Isystem is not appropriate
for conditions where LOW range is recommended. Refer
to “Off-Road Driving Tips” in this section.
Quadra-Trac IIOperating
Instructions/Precautions — If Equipped
The Quadra-Trac IItransfer case is fully automatic in the
normal driving 4 HI mode. The Quadra-Trac IItransfer
case provides three mode positions — four wheel drive
high range, neutral, and four wheel drive low range.
This transfer case is fully automatic in the 4 HI mode.
This transfer case divides engine torque almost evenly
with 48 percent of engine torque to the front axle and 52
percent of engine torque to the rear axle. When speed
differences are increased between the front and rear driveshafts, the transfer case can transmit up to 100 percent of
available engine torque to the front or rear drive shafts.
When additional traction is required, the 4 LOW position
can be used to lock the front and rear driveshafts together
and force the front and rear wheels to rotate at the same
speed. The 4 LOW position is intended for loose, slippery
road surfaces only. Driving in the 4 LOW position on dry
hard surfaced roads may cause increased tire wear and
damage to driveline components.
When operating your vehicle in 4 LOW, the engine speed
is approximately three times that of the 4 HI 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.
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To release the parking brake, pull up slightly, press the
center button, then lower the lever completely.
Be sure the parking brake is fully disengaged before
driving. Failure to do so can lead to brake failure.
NOTE:Parking brake adjustment and maintenance
should be performed by your authorized dealer.
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.
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build up between the tire tread and the road. This
hydroplaning action can cause loss of traction, braking
ability, and control.
•After going through deep water or a car wash, brakes
may become wet, resulting in decreased performance
and unpredictable braking action. Dry the brakes by
gentle, intermittent pedal action while driving at very
slow speeds.
VARI-LOK REAR AXLE — IF EQUIPPED
The optional Vari-Lok axle is fully automatic and requires
no driver input to operate. Under normal driving condi-
tions the unit functions as a standard axle balancing
torque evenly between left and right wheels. With a
traction difference between left and right wheels the
coupling will sense a speed difference. As one wheel
begins to spin faster than the other, torque will automati-
cally transfer from the wheel that has less traction to the
wheel that has traction.
ON-ROAD DRIVING TIPS
Utility vehicles have higher ground clearance and a
narrower track to make them capable of performing in a
wide variety of off-road applications. Specific design
characteristics give them a higher center of gravity than
ordinary cars.
An advantage of the higher ground clearance is a better
view of the road, allowing you to anticipate problems.
They are not designed for cornering at the same speeds as
conventional 2-wheel drive vehicles any more than low-
slung sports cars are designed to perform satisfactorily in
off-road conditions. If at all possible, avoid sharp turns or
abrupt maneuvers. As with other vehicles of this type,
failure to operate this vehicle correctly may result in loss
of control or vehicle rollover.
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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 do
not let anyone near a spinning wheel no matter what
the speed.
266 STARTING AND OPERATING

colored Indicator Lamp. A sensor is located in the spare
wheel if the vehicle is equipped with a matching full size
spare wheel and tire assembly.
NOTE:For vehicles with optional wheel/tire sizes and
significantly different tire placard pressures, the placard
pressure value and the low-pressure threshold value is
re-programmable at your authorized dealer to accommo-
date the customer selected wheel/tire combinations rec-
ommended by DaimlerChrysler Corporation.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 system operation or sen-
sor damage may result when using replacement
equipment that is not of the same size, type, and/or
style. After-market wheels can cause sensor damage.
Do not use tire sealant from a can, or balance beads
if your vehicle is equipped with a TPM system, as
damage to the sensors may result.
270 STARTING AND OPERATING

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 system operation or sen-
sor damage may result when using replacement
equipment that is not of the same size, type, and/or
style. After-market wheels can cause sensor damage.
Do not use tire sealant from a can, or balance beads
if your vehicle is equipped with a TPM system, as
damage to the sensors may result.
CAUTION!
After inspecting or adjusting the tire pressure al-
ways reinstall the valve stem cap. This will prevent
moisture and dirt from entering the valve stem,
which could damage the wheel rim sensor.
NOTE:
•The TPM system can inform the driver of a low tire
pressure condition.
•The TPM system is not intended to replace normal tire
care and maintenance, nor to provide warning of a tire
failure or condition.
•The TPM system should not be used as a tire pressure
gauge while adjusting your tire pressure.
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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 “Maintenance Schedules”
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 per-
formed.NOTE:The Premium Tire Pressure Monitor System will
automatically locate the pressure values displayed in the
correct vehicle position following a tire rotation.
The suggested rotation method is the “forward-cross”
shown in the following diagram.
276 STARTING AND OPERATING

manual. When your vehicle is used for trailer towing,
never exceed the gross axle weight rating (GAWR) by the
addition of:
•The tongue weight of the trailer.
•The weight of any other type of cargo or equipment
put in or on your vehicle.
WARNING!
Improper towing can lead to an injury accident.
Follow these guidelines to make your trailer towing
as safe as possible:
•Be 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 ofthe vehicle and trailer. Failure to load trailers heavier
in front is the cause of many trailer related accidents.
•Donotinterconnect the hydraulic brake system of
your vehicle with that of the trailer. This could cause
inadequate braking and possible personal injury.
•Trailer brakes are required for trailers in excess of
2,000 lbs (907 kg).
•Donotconnect 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.
•When 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.
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