JEEP GRAND CHEROKEE 2012 WK2 / 4.G SRT Owners Manual

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 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.
•Temporary spare tires are spares designed for tempo-
rary emergency use only. Temporary high pressure
compact spare tires have the letter “T” or “S” molded
into the sidewall preceding the size designation. Ex-
ample: 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.
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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
TorS= 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)
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EXAMPLE:
Service Description:
95= Load Index
— A numerical code associated with the maximum load a tire can carry
H= Speed Symbol
— A symbol indicating the range of speeds at which a tire can carry a load corresponding
to its load index under certain operating conditions
— The maximum speed corresponding to the speed symbol should only be achieved under
specified operating conditions (i.e., tire pressure, vehicle loading, road conditions, and
posted speed limits)
Load Identification:
....blank....= Absence of any text on the sidewall of the tire indicates a Standard Load (SL) tire
Extra Load (XL)= Extra load (or reinforced) tire
Light Load (LL)= Light load tire
C, D, E, F, G= Load range associated with the maximum load a tire can carry at a specified pressure
Maximum Load— Maximum load indicates the maximum load this tire is designed to carry
Maximum Pressure— 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 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
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Tire Terminology And Definitions
Term Definition
B-PillarThe vehicle B-Pillar is the structural member of the body located
behind the front door.
Cold Tire Inflation PressureCold 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 (1.6 km) after sitting for a three hour period. Inflation
pressure is measured in units of PSI (pounds per square inch) or
kPa (kilopascals).
Maximum Inflation PressureThe maximum inflation pressure is the maximum permissible cold
tire inflation pressure for this tire. The maximum inflation pres-
sure is molded into the sidewall.
Recommended Cold Tire Inflation Pres-
sureVehicle manufacturer’s recommended cold tire inflation pressure
as shown on the tire placard.
Tire PlacardA paper label permanently attached to the vehicle describing the
vehicle’s loading capacity, the original equipment tire sizes and
the recommended cold tire inflation pressures.
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Tire Loading And Tire Pressure
Tire And Loading Information Placard Location
NOTE:The proper cold tire inflation pressure is listed
on the driver ’s side B-Pillar or the rear edge of the
driver’s side door.
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.
Tire Placard Location
Tire and Loading Information Placard
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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 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
axles must not be exceeded. For further information on
GAWRs, vehicle loading, and trailer towing, refer to
“Vehicle Loading” in this section.
To determine the maximum loading conditions of your
vehicle, locate the statement “The combined weight of
occupants and cargo should never exceed XXX lbs or
XXX kg” on the Tire and Loading Information placard.The combined 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 “The combined weight of occu-
pants and cargo should never exceed XXX lbs or XXX kg”
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 lbs or XXX kg.
4. The resulting figure equals the available amount of
cargo and luggage load capacity. For example, if “XXX”
amount equals 1,400 lbs (635 kg) and there will be five
150 lb (68 kg) passengers in your vehicle, the amount of
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available cargo and luggage load capacity is 650 lbs
(295 kg) (since 5 x 150 = 750, and 1400 – 750 = 650 lbs
[295 kg]).
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 calcu-
late total load, cargo/luggage, and towing capacities
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.
•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 — 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 collisions.
•Under-inflation increases tire flexing and can re-
sult in over-heating and tire failure.
•Over-inflation reduces a tire’s ability to cushion
shock. Objects on the road and chuckholes can
cause damage that result in tire failure.
•Over-inflated or under-inflated tires can affect
vehicle handling and can fail suddenly, resulting
in loss of vehicle control.
•Unequal tire pressures can cause steering prob-
lems. You could lose control of your vehicle.
(Continued)
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