2005 JEEP GRAND CHEROKEE Owners Manual

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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OFF-ROAD DRIVING TIPS
NOTE:Prior to off-road driving, remove the front air
dam to prevent damage. The front air dam is attached to
the lower front fascia with quarter turn fasteners, and can
be removed by hand.
When To Use 4WD LOW Range — If Equipped
When off-road driving, shift to 4WD LOW for additional
traction. This range should be limited to extreme situa-
tions such as deep snow, mud, or sand where additional
low speed pulling power is needed. Vehicle speeds in
excess of 25 mph (40 km/h) should be avoided when in
4WD LOW range.
Driving Through Water
Although your vehicle is capable of driving through
water, there are a number of precautions that must be
considered before entering the water:
CAUTION!
When driving through water, do not exceed 5 mph (8
km/h). Always check water depth before entering as
a precaution, and check all fluids afterward. Driving
through water may cause damage that may not be
covered by the new vehicle limited warranty.
Driving through water more than a few inches deep will
require extra caution to ensure safety and prevent dam-
age to your vehicle. If you must drive through water, try
to determine the depth and the bottom condition (and
location of any obstacles) prior to entering. Proceed with
caution and maintain a steady controlled speed less than
5 mph (8 km/h) in deep water to minimize wave effects.
Flowing Water
If the water is swift flowing and rising (as in storm
run-off) avoid crossing until the water level recedes
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and/or the flow rate is reduced. If you must cross
flowing water avoid depths in excess of 9 inches. The
flowing water can erode the streambed causing your
vehicle to sink into deeper water. Determine exit point(s)
that are downstream of your entry point to allow for
drifting.
Standing Water
Avoid driving in standing water deeper than 20 inches,
and reduce speed appropriately to minimize wave ef-
fects. Maximum speed in 20 inches of water is less than 5
mph (8 km/h).
Maintenance
After driving through deep water, inspect your vehicle
fluids and lubricants (engine oil, transmission oil, axle,
transfer case) to assure the fluids have not been contami-
nated. Contaminated fluid (milky, foamy in appearance)
should be flushed/changed as soon as possible to pre-
vent component damage.Driving In Snow, Mud and Sand
In heavy snow, when pulling a load, or for additional
control at slower speeds, shift the transmission to a low
gear and shift the transfer case to 4WD LOW if necessary.
Refer to “Four-Wheel Drive Operation” in this section.
Do not shift to a lower gear than necessary to maintain
headway. Over-revving the engine can spin the wheels
and traction will be lost.
Avoid abrupt downshifts on icy or slippery roads, be-
cause engine braking may cause skidding and loss of
control.
Hill Climbing
NOTE:Before attempting to climb a hill, determine the
conditions at the crest and/or on the other side.
Before climbing a steep hill,shift the transmission to a
lower gear and shift the transfer case to 4WD LOW. Use
first gear and 4WD LOW for very steep hills.
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If you stall or begin to lose headwaywhile climbing a
steep hill, allow your vehicle to come to a stop and
immediately apply the brakes. Restart the engine and
shift to R (Reverse). Back slowly down the hill allowing
the compression braking of the engine to help regulate
your speed. If the brakes are required to control vehicle
speed, apply them lightly and avoid locking or skidding
the tires.
WARNING!
If the engine stalls or you lose headway or cannot
make it to the top of a steep hill or grade, never
attempt to turn around. To do so may result in
tipping and rolling the vehicle. Always back care-
fully straight down a hill in R (Reverse) gear. Never
back down a hill in N (Neutral) using only the brake.
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.
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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.
•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.
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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:This system must be reset if the vehicle battery
is disconnected. See your authorized dealer for service.
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.
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•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 begins with the tire diameter molded
into the sidewall. Example: 31x10.5 R15 LT.
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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 Milimeters (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)
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