JEEP GRAND CHEROKEE 2007 WK / 3.G Owners Manual

Remember, never drive diagonally across a hill-always
drive straight up or down.
If the wheels start to slip as you approach the crest of a
hill, ease off the accelerator and maintain headway by
turning the front wheels slowly. This may provide a fresh
“bite” into the surface and will usually provide traction
to complete the climb.
Traction Downhill
Shift the transmission into a low gear and the transfer
case to 4WD LOW range. Let the vehicle go slowly down
the hill with all four wheels turning against engine
compression drag. This will permit you to control the
vehicle speed and direction.
When descending mountains or hills, repeated braking
can cause brake fade with loss of braking control. Avoid
repeated heavy braking by downshifting the transmis-
sion whenever possible.
After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road it is
always a good idea to check for damage. That way you
can get any problems taken care of right away and have
your vehicle ready when you need it.
•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
•Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
•Check for accumulations of plants or brush. These
things could be a fire hazard. They might hide damage
to fuel lines, brake hoses, axle pinion seals, and
propeller shafts.
STARTING AND OPERATING 271
5

•After extended operation in mud, sand, water, or
similar dirty conditions, have brake rotors, wheels,
brake linings, and axle yokes inspected and cleaned as
soon as possible.
WARNING!
Abrasive material in any part of the brakes may
cause excessive wear or unpredictable braking. You
might not have full braking power when you need it
to prevent an accident. If you have been operating
your vehicle in dirty conditions, get your brakes
checked and cleaned as necessary.
•If you experience unusual vibration after driving in
mud, slush or similar conditions, check the wheels for
impacted material. Impacted material can cause a
wheel imbalance and freeing the wheels of it will
correct the situation.
PARKING BRAKE
To set the parking brake, pull the lever up as firmly as
possible. When the parking brake is applied with the
ignition ON, the “Brake Warning Light” in the instru-
ment cluster will light. To release the parking brake, pull
up slightly, press the center button, then lower the lever
completely.
NOTE:The instrument cluster “Brake Warning Light”
indicates only that the parking brake is applied. It does
not indicate the degree of brake application.
272 STARTING AND OPERATING

Be sure the parking brake is firmly set when parked and
the gear shift lever is in the P (Park) position. When
parking on a hill, you should apply the parking brake
before placing the gear shift lever in P (Park), otherwise
the load on the transmission locking mechanism may
make it difficult to move the selector out of P (Park).
WARNING!
•Always fully apply the parking brake when leav-
ing your vehicle, or it may roll and cause damage
or injury. Also, be certain to leave the transmis-
sion in P (Park). Failure to do so may allow the
vehicle to roll and cause damage or injury.
•Leaving children in a vehicle unattended is dan-
gerous for a number of reasons. A child or others
could be injured. Children should be warned not
to touch the parking brake or the gear selector
lever. Don’t leave the keys in the ignition. A child
could operate power windows, other controls, or
move the vehicle.
•Be sure the parking brake is fully disengaged
before driving, failure to do so can lead to brake
problems due to excessive heating of the rear
brakes.
Parking Brake
STARTING AND OPERATING 273
5

When parking on a hill, turn the front wheels toward the
curb on a downhill grade and away from the curb on an
uphill grade.
The parking brake should always be applied whenever
the driver is not in the vehicle.
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.
274 STARTING AND OPERATING

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.
WARNING!
•The Anti-Lock Brake System (ABS) cannot pre-
vent the natural laws of physics from acting on the
vehicle, nor can it increase braking or steering
efficiency beyond that afforded by the condition
of the vehicle brakes and tires or the traction
afforded.
•The ABS cannot prevent accidents, including
those resulting from excessive speed in turns,
following another vehicle too closely, or hydro-
planing. Only a safe, attentive, and skillful driver
can prevent accidents.
•The capabilities of an ABS equipped vehicle must
never be exploited in a reckless or dangerous
manner which could jeopardize the user’s safety
or the safety of others.
STARTING AND OPERATING 275
5

CAUTION!
The Anti-Lock Brake System is subject to possible
detrimental effects of electronic interference caused
by improperly installed after-market radios or tele-
phones.
NOTE:During severe braking conditions, a pulsing
sensation may occur and a clicking noise will be heard.
This is normal, indicating that the Anti-Lock Brake
System is functioning.
WARNING!
To use your brakes and accelerator more safely,
follow these tips:
•Do not “ride” the brakes by resting your foot on the
pedal. This could overheat the brakes and result in
unpredictable braking action, longer stopping dis-
tances, or brake damage.
•When descending mountains or hills, repeated brak-
ing can cause brake fade with loss of braking control.
Avoid repeated heavy braking by downshifting the
transmission or locking out overdrive whenever pos-
sible.
•Engines may idle at higher speeds during warm-up,
which could cause rear wheels to spin and result in
loss of vehicle control. Be especially careful while
driving on slippery roads, in close-quarter maneuver-
ing, parking or stopping.
•Do not drive too fast for road conditions, especially
when roads are wet or slushy. A wedge of water can
276 STARTING AND OPERATING

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.
POWER STEERING
The standard power steering system will give you good
vehicle response and increased ease of maneuverability
in tight spaces. The system will provide mechanical
steering capability if power assist is lost.
If for some reason the power assist is interrupted, it will
still be possible to steer your vehicle. Under these condi-
tions, you will observe a substantial increase in steering
effort, especially at very low vehicle speeds and during
parking maneuvers.NOTE:Increased noise levels at the end of the steering
wheel travel are considered normal and do not indicate
that there is a problem with the power steering system.
Upon initial start-up in cold weather, the power steering
pump may make noise for a short amount of time. This is
due to the cold, thick fluid in the steering system. This
noise should be considered normal, and does not in any
way damage the steering system.WARNING!
Continued operation with reduced power steering
assist could pose a safety risk to yourself and others.
Service should be obtained as soon as possible.
STARTING AND OPERATING 277
5

CAUTION!
Prolonged operation of the steering system at the
end of the steering wheel travel will increase the
steering fluid temperature and it should be avoided
when possible. Damage to the power steering pump
may occur.
MULTI DISPLACEMENT SYSTEM (MDS) - 5.7L
Engine Only
This feature offers improved fuel economy by shutting
off four of the engine’s eight cylinders during light load
and cruise conditions. The system is automatic with no
driver inputs or additional driving skills required.
NOTE:The MDS system may take some time to return
to full functionality after a battery disconnect.
TIRE SAFETY INFORMATION
Tire Markings
NOTE:
•P (Passenger)-Metric tire sizing is based on U.S. design
standards. P-Metric tires have the letter “P” molded
into the sidewall preceding the size designation. Ex-
ample: P215/65R15 95H.
278 STARTING AND OPERATING

•European Metric tire sizing is based on European
design standards. Tires designed to this standard have
the tire size molded into the sidewall beginning with
the section width. The letterPis absent from this tire
size designation. Example: 215/65R15 96H
•LT (Light Truck)-Metric tire sizing is based on U.S.
design standards. The size designation for LT-Metric
tires is the same as for P-Metric tires except for the
letters “LT” that are molded into the sidewall preced-
ing the size designation. Example: LT235/85R16.
•Temporary Spare tires are high-pressure compact
spares designed for temporary emergency use only.
Tires designed to this standard have the letter “T”
molded into the sidewall preceding the size designa-
tion. Example: T145/80D18 103M.
•High Flotation tire sizing is based on U.S. design
standards and it begins with the tire diameter molded
into the sidewall. Example: 31x10.5 R15 LT.
STARTING AND OPERATING 279
5

Tire Sizing Chart
EXAMPLE:
Size Designation:
P= Passenger car tire size based on U.S. design standards
....blank....= Passenger car tire based on European design standards
LT= Light Truck tire based on U.S. design standards
T= Temporary Spare tire
31= Overall Diameter in Inches (in)
215= Section Width in Millimeters (mm)
65= Aspect Ratio in Percent (%)
—Ratio of section height to section width of tire.
10.5= Section Width in Inches (in)
R= Construction Code
—Rmeans Radial Construction.
—Dmeans Diagonal or Bias Construction.
15= Rim Diameter in Inches (in)
280 STARTING AND OPERATING