JEEP GRAND CHEROKEE 2008 WK / 3.G Owners Manual

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 (%)
ÐRatio of section height to section width of tire.
10.5= Section Width in Inches (in)
R= Construction Code
Ð9R9means Radial Construction.
Ð9D9means Diagonal or Bias Construction.
15= Rim Diameter in Inches (in)
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EXAMPLE:
Service Description:
95= Load Index
ÐA numerical code associated with the maximum load a tire can carry.
H= Speed Symbol
ÐA symbol indicating the range of speeds at which a tire can carry a load corresponding
to its load index under certain operating conditions.
ÐThe maximum speed corresponding to the Speed Symbol should only be achieved un-
der specified operating conditions (i.e. tire pressure, vehicle loading, road conditions, and
posted speed limits).
Load Identification:
(....blank....(= Absence of any text on sidewall of the tire indicates a Standard Load (SL) Tire
Extra Load (XL)= Extra Load (or Reinforced) Tire
Light Load= Light Load Tire
C,D,E= Load range associated with the maximum load a tire can carry at a specified pressure
Maximum LoadÐ Maximum Load indicates the maximum load this tire is designed to carry.
Maximum PressureÐ
Maximum Pressure indicates the maximum permissible cold tire inflation pressure for this tire.
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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 date codelocated 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
ÐThis 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. (2 digits)
L9= Code representing the tire size. (2 digits)
ABCD= Code used by tire manufacturer. (1 to 4 digits)
03= Number representing the week in which the tire was manufactured. (2 digits)
Ð03 means the 3rd week.
01= Number representing the year in which the tire was manufactured. (2 digits)
Ð01 means the year 2001.
ÐPrior to July 2000, tire manufacturers were only required to have 1 number to represent the year in
which the tire was manufactured. Example: 031 could represent the 3rd week of 1981 or 1991.
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Tire Loading and Tire Pressure
Tire Placard Location
NOTE:The proper cold tire inflation pressure is listed
on either the face of the driver's door or the driver's side
ªBº 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) the total weight your vehicle can carry
3) the tire size designed for your vehicle
4) the cold tire inflation pressures for the front, rear,
and spare tires.
Tire Placard Location
Tire and Loading Information
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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 ªTire and Loading
Informationº placard and in the ªVehicle Loadingº sec-
tion of this manual.
NOTE:Under a maximum loaded vehicle condition,
gross axle weight ratings (GAWR's) for the front and rear
axles must not be exceeded. For further information on
GAWR's, vehicle loading, and trailer towing, refer to the
ªVehicle Loadingº section of this manual.
To determine the maximum loading conditions of your
vehicle, locate the statement ªThe combined weight of
occupants and cargo should never exceed XXX kg or XXX
lbs.º on the Tire and Loading Information placard. Thecombined weight of occupants, cargo/luggage and
trailer tongue weight (if applicable) should never exceed
the weight referenced here.
Steps for Determining Correct Load Limit
1. Locate the statement ªThe combined weight of occu-
pants and cargo should never exceed XXX poundsº on
your vehicle's placard.
2. Determine the combined weight of the driver and
passengers that will be riding in your vehicle.
3. Subtract the combined weight of the driver and pas-
sengers from XXX kilograms or XXX pounds.
4. The resulting figure equals the available amount of
cargo and luggage load capacity. For example, if ªXXXº
amount equals 1400 lbs. and there will be five 150 lb.
passengers in your vehicle, the amount of available cargo
and luggage load capacity is 650 lbs. (since 5 x 150 = 750,
and 1400 ± 750 = 650 lbs.)
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5. Determine the combined weight of luggage and cargo
being loaded on the vehicle. That weight may not safely
exceed the available cargo and luggage load capacity
calculated in Step 4.
6. If your vehicle will be towing a trailer, load from your
trailer will be transferred to your vehicle. Consult this
manual to determine how this reduces the available
cargo and luggage load capacity of your vehicle.NOTE:The following table shows examples on how to
calculate total load, cargo/luggage, and towing capaci-
ties of your vehicle with varying seating configurations
and number and size of occupants. This table is for
illustration purposes only and may not be accurate for
the seating and load carry capacity of your vehicle.
NOTE:For the following example, the combined weight
of occupants and cargo should never exceed 865 lbs. (392
kg).
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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 Ð 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:1. SafetyÐ
WARNING!
²Improperly inflated tires are dangerous and can
cause accidents.
²Under inflation increases tire flexing and can result
in tire failure.
²Over inflation reduces a tire's ability to cushion
shock. Objects on the road and chuckholes can cause
damage that result in tire failure.
²Unequal tire pressures can cause steering problems.
You could lose control of your vehicle.
²Over inflated or under inflated tires can affect
vehicle handling and can fail suddenly, resulting in
loss of vehicle control.
²Unequal tire pressures from one side of the vehicle to
the other can cause the vehicle to drift to the right or
left.
²Always drive with each tire inflated to the recom-
mended cold tire inflation pressure.
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2. EconomyÐ
Improper inflation pressures can cause uneven wear
patterns to develop across the tire tread. These abnormal
wear patterns will reduce tread life resulting in a need for
earlier tire replacement. Under inflation also increases
tire rolling resistance and results in higher fuel consump-
tion.
3. Ride Comfort and Vehicle StabilityÐ
Proper tire inflation contributes to a comfortable ride.
Over inflation produces a jarring and uncomfortable ride.
Both under inflation and over inflation affect the stability
of the vehicle and can produce a feeling of sluggish
response or over responsiveness in the steering.
Unequal tire pressures can cause erratic and unpredict-
able steering response.
Unequal tire pressure from side to side may cause the
vehicle to drift left or right.Tire Inflation Pressures
The proper cold tire inflation pressure is listed on either
the face of the driver's door or the driver's side ªBº pillar.
The pressure should be checked and adjusted as well as
inspecting for signs of tire wear or visible damage at least
once a month. Use a good quality pocket-type gauge to
Tire Placard Location
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check tire pressure. Do not make a visual judgement
when determining proper inflation. Radial tires may look
properly inflated even when they are under inflated.
CAUTION!
After inspecting or adjusting the tire pressure, al-
ways reinstall the valve stem cap (if equipped). This
will prevent moisture and dirt from entering the
valve stem, which could damage the valve stem.
Inflation pressures specified on the placard are always
ªcold tire inflation pressure.º Cold tire inflation pressure
is defined as the tire pressure after the vehicle has not
been driven for at least 3 hours, or driven less than 1 mile
(1 km) after a 3 hour period. The cold tire inflation
pressure must not exceed the maximum inflation pres-
sure molded into the tire sidewall.Check tire pressures more often if subject to a wide range
of outdoor temperatures, as tire pressures vary with
temperature changes.
Tire pressures change by approximately 1 psi (7 kPa) per
12É F (7É C) of air temperature change. Keep this in mind
when checking tire pressure inside a garage, especially in
the winter.
Example: If garage temperature = 68É F (20É C) and the
outside temperature = 32É F (0É C) then the cold tire
inflation pressure should be increased by 3 psi (21 kPa),
which equals 1 psi (7 kPa) for every 12É F (7É C) for this
outside temperature condition.
Tire pressure may increase from 2 to 6 psi (13 to 40 kPa)
during operation. DO NOT reduce this normal pressure
build up or your tire pressure will be too low.
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