JEEP COMMANDER 2009 1.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 (%)
— 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= Light load tire
C, D, E= 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 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
axles must not be exceeded. For further information on
GAWRs, vehicle loading, and trailer towing, refer to
“Vehicle Loading” in this section.
Tire and Loading Information Placard
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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
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.
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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 capacitiesof 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 occu-
pants 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 accidents.
(Continued)
WARNING! (Continued)
•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.
•Unequal tire pressures from one side of the vehicle
to the other can cause the vehicle to drift to the right
or left.
•Always drive with each tire inflated to the recom-
mended cold tire inflation pressure.
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Economy
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. Underinflation also increases tire
rolling resistance and results in higher fuel consumption.
Ride Comfort and Vehicle Stability
Proper tire inflation contributes to a comfortable ride.
Overinflation produces a jarring and uncomfortable ride.
Both underinflation and overinflation 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 the
driver’s side “B” Pillar.
The pressure should be checked and adjusted, as well as
inspected for signs of tire wear or visible damage, at least
once a month. Use a good quality pocket-type gauge to
check tire pressure. Do not make a visual judgement
when determining proper inflation. Radial tires may look
properly inflated even when they are underinflated.
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 it.
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Inflation pressures specified on the placard are always
cold tire inflation pressure. Cold tire inflation pressure is
defined as the tire pressure after the vehicle has not been
driven for at least three hours, or driven less than 1 mile
(1.6 km) after a three-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
12°F (7°C) of air temperature change. Keep this in mind
when checking tire pressure inside a garage, especially in
the winter.
Example: If garage temperature = 68°F (20°C) and the
outside temperature = 32°F (0°C) then the cold tireinflation pressure should be increased by 3 psi (21 kPa),
which equals 1 psi (7 kPa) for every 12°F (7°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.
Tire Pressures For High Speed Operation
The manufacturer advocates driving at safe speeds
within posted speed limits. Where speed limits or condi-
tions are such that the vehicle can be driven at high
speeds, maintaining correct tire inflation pressure is very
important. Increased tire pressure and reduced vehicle
loading may be required for high-speed vehicle opera-
tion. Refer to original equipment or an authorized tire
dealer for recommended safe operating speeds, loading
and cold tire inflation pressures.
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