2009 JEEP GRAND CHEROKEE tires

Traction Downhill
Shift the transmission into a low gear, and the transfer
case into 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.
•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.
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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 ABS 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 ABS 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.
•The ABS cannot prevent the natural laws of phys-
ics from acting on the vehicle, nor can it increase
braking or steering efficiency beyond that af-
forded by the condition of the vehicle brakes and
tires or the traction afforded.
(Continued)
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•Understeer - when the vehicle is turning less than
appropriate for the steering wheel position.
The ESP/TCS Indicator Light located in the instrument
cluster, starts to flash as soon as the tires lose traction and
the ESP system becomes active. The ESP/TCS Indicator
Light also flashes when TCS is active. If the ESP/TCS
Indicator Light begins to flash during acceleration, ease
up on the accelerator and apply as little throttle as
possible. Be sure to adapt your speed and driving to the
prevailing road conditions.WARNING!
ESP (Electronic Stability Program) cannot prevent the
natural laws of physics from acting on the vehicle,
nor can it increase the traction afforded by prevailing
road conditions. ESP cannot prevent accidents, in-
cluding those resulting from excessive speed in
turns, driving on very slippery surfaces, or hydro-
planing. Only a safe, attentive, and skillful driver can
prevent accidents. The capabilities of an ESP-
equipped vehicle must never be exploited in a reck-
less or dangerous manner which could jeopardize the
user’s safety or the safety of others.
The ESP system has three available operating modes in
4WD HIGH range, two available operating modes on
2WD vehicles, and one operating mode in 4WD LOW
range.
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TIRE SAFETY INFORMATION
Tire MarkingsNOTE:
•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 designa-
tion. Example: P215/65R15 95H.
•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.
1 — U.S. DOT Safety Stan-
dards Code (TIN)4 — Maximum Load
2 — Size Designation 5 — Maximum Pressure
3 — Service Description 6 — Treadwear, Traction and
Temperature Grades 326 STARTING AND OPERATING

•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.
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)
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Tire Identification Number (TIN)
The TIN may be found on one or both sides of the tire,
however, the date code may only be on one side. Tires
with white sidewalls will have the full TIN, including the
date code, located on the white sidewall side of the tire.Look for the TIN on the outboard side of black sidewall
tires as mounted on the vehicle. If the TIN is not found on
the outboard side, then you will find it on the inboard
side of the tire.
EXAMPLE:
DOT MA L9 ABCD 0301
DOT= Department of Transportation
— This symbol certifies that the tire is in compliance with the U.S. Department of Transportation tire
safety standards and is approved for highway use
MA= Code representing the tire manufacturing location (two digits)
L9= Code representing the tire size (two digits)
ABCD= Code used by the tire manufacturer (one to four digits)
03= Number representing the week in which the tire was manufactured (two digits)
—03 means the 3rd week.
01= Number representing the year in which the tire was manufactured (two digits)
—01 means the year 2001
— Prior to July 2000, tire manufacturers were only required to have one number to represent the year
in which the tire was manufactured. Example: 031 could represent the 3rd week of 1981 or 1991
330 STARTING AND OPERATING

Tire Loading and Tire Pressure
Tire Placard Location
NOTE:The proper cold tire inflation pressure is listed
on the driver’s side B-Pillar.
Tire and Loading Information Placard
This placard tells you important information about
the:
1) number of people that can be carried in the vehicle
2) total weight your vehicle can carry
3) tire size designed for your vehicle
4) cold tire inflation pressures for the front, rear, and
spare tires.
Loading
The vehicle maximum load on the tire must not exceed
the load carrying capacity of the tire on your vehicle. You
will not exceed the tire’s load carrying capacity if you
adhere to the loading conditions, tire size, and cold tire
inflation pressures specified on the Tire and Loading
Information placard and in the “Vehicle Loading” section
of this manual.
NOTE:Under a maximum loaded vehicle condition,
gross axle weight ratings (GAWRs) for the front and rear
Tire and Loading Information Placard
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WARNING!
Overloading of your tires is dangerous. Overloading
can cause tire failure, affect vehicle handling, and
increase your stopping distance. Use tires of the
recommended load capacity for your vehicle. Never
overload them.
TIRES — GENERAL INFORMATION
Tire Pressure
Proper tire inflation pressure is essential to the safe and
satisfactory operation of your vehicle. Three primary
areas are affected by improper tire pressure:
Safety
WARNING!
•Improperly inflated tires are dangerous and can
cause accidents.
•Underinflation increases tire flexing and can result
in tire failure.
•Overinflation reduces a tire’s ability to cushion
shock. Objects on the road and chuckholes can cause
damage that result in tire failure.
•Unequal tire pressures can cause steering prob-
lems. You could lose control of your vehicle.
•Overinflated or underinflated tires can affect ve-
hicle handling and can fail suddenly, resulting in
loss of vehicle control.
(Continued)
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