Jeep Grand Cherokee SRT8 (2009 year). Instruction

EXAMPLE:

Service Description:

= Load Index

— A numerical code associated with the maximum load a tire can carry

= 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:

ⴖ....blank....ⴖ = 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

= Code representing the tire manufacturing location (two digits)

= Code representing the tire size (two digits)

ABCD

= Code used by the tire manufacturer (one to four digits)

= Number representing the week in which the tire was manufactured (two digits)

—03 means the 3rd week.

= 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.

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

Run Flat Tires

This vehicle is equipped with run flat tires. Although the
tires are designed with a “run flat” feature that allows the
vehicle to be driven about 50 miles (80 km) at 55 mph
(88 km/h), immediate service should be obtained.

WARNING!

Do not exceed 50 mph (80 km/h) if the “Tire Pressure
Monitoring Telltale Light” is illuminated. Vehicle
handling and braking may be reduced. You could
have an accident and be severely or fatally injured.

NOTE:

The “run flat” feature eliminates the need for a

spare tire or jack. This vehicle is not equipped with either
a spare tire or jack.

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:

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Safety

WARNING!

• Improperly inflated tires are dangerous and can

cause accidents.

• Under inflation increases tire flexing and can

result in tire failure.

• Over inflation reduces a tire’s ability to cushion

shock. Objects on the road and chuck holes can
cause damage that results in tire failure.

• Unequal tire pressures can cause steering prob-

lems. You could lose control of your vehicle.

• Overinflated or under inflated tires can affect

vehicle handling and can fail suddenly, resulting
in loss of vehicle control.

(Continued)

WARNING! (Continued)

• Unequal tire pressures from one side of the ve-

hicle to the other can cause the vehicle to drift to
the right or left.
Always drive with each tire properly inflated.

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. Under inflation also increases
tire rolling resistance and results in higher fuel
consumption.

Ride Comfort and Vehicle Stability
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

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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
inspecting 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 under inflated.

CAUTION!

After inspecting or adjusting the tire pressure always
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
“cold tire inflation pressure”. 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 side wall.

Check tire pressures more often if subject to a wide range
of outdoor temperatures, as tire pressures vary with
temperature changes.

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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 tire
inflation 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.

WARNING!

High speed driving with your vehicle under maxi-
mum load is dangerous. The added strain on your
tires could cause them to fail. You could have a
serious accident. Don’t drive a vehicle loaded to the
maximum capacity at continuous speeds above
75 mph (120 km/h).

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Radial-Ply Tires

WARNING!

Combining radial ply tires with other types of tires
on your vehicle will cause your vehicle to handle
poorly. The instability could cause an accident. Al-
ways use radial tires in sets of four. Never combine
them with other types of tires.

Cuts and punctures in radial tires are repairable only in
the tread area because of sidewall flexing. Consult your
dealer for radial tire repairs.

Tire Spinning

When stuck in mud, sand, snow, or ice conditions, do not
spin your vehicle’s wheels above 35 mph (55 km/h).

WARNING!

Fast spinning tires can be dangerous. Forces gener-
ated by excessive wheel speeds may cause tire dam-
age or failure. A tire could explode and injure some-
one. Do not spin your vehicle’s wheels faster than
35 mph (55 km/h) when you are stuck, and do not let
anyone near a spinning wheel no matter what the
speed.

Tread Wear Indicators

Tread wear indicators are in the original equipment tires
to help you in determining when your tires should be
replaced.

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These indicators are molded into the bottom of the tread
grooves and will appear as bands when the tread depth
becomes 1/16 inch (2 mm). When the indicators appear
in 2 or more adjacent grooves, the tire should be replaced.

Many states have laws requiring tire replacement at this
point.

Life of Tire

The service life of a tire is dependent upon varying
factors including but not limited to:

• Driving style
• Tire pressure
• Distance driven

WARNING!

All tires should be replaced after six years, regardless
of the remaining tread. Failure to follow this warning
can result in sudden tire failure. You could lose
control and have an accident resulting in serious
injury.

1 — Worn Tire
2 — New Tire

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Keep unmounted tires in a cool, dry place with as little
exposure to light as possible. Protect tires from contact
with oil, grease and gasoline.

Replacement Tires

The tires on your new vehicle provide a balance of many
characteristics. They should be inspected regularly for
wear and correct cold tire inflation pressure. The manu-
facturer strongly recommends that you use tires equiva-
lent to the originals in size, quality and performance
when replacement is needed (see the paragraph on tread
wear indicators). Refer to the Tire and Loading Informa-
tion placard for the size designation of your tire. The
service description and load identification will be found
on the original equipment tire. Failure to use equivalent
replacement tires may adversely affect the safety, han-
dling, and ride of your vehicle. We recommend that you
contact your original equipment or an authorized tire
dealer with any questions you may have on tire specifi-
cations or capability.

WARNING!

• Do not use a tire, wheel size or rating other than

that specified for your vehicle. Some combinations
of unapproved tires and wheels may change sus-
pension dimensions and performance characteris-
tics, resulting in changes to steering, handling, and
braking of your vehicle. This can cause unpredict-
able handling and stress to steering and suspen-
sion components. You could lose control and have
an accident resulting in serious injury or death.
Use only the tire and wheel sizes with load ratings
approved for your vehicle.

• Never use a tire with a smaller load index or

capacity, other than what was originally equipped
on your vehicle. Using a tire with a smaller load
index could result in tire overloading and failure.
You could lose control and have an accident.

(Continued)

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WARNING! (Continued)

• Failure to equip your vehicle with tires having

adequate speed capability can result in sudden tire
failure and loss of vehicle control.

CAUTION!

Replacing original tires with tires of a different size
may result in false speedometer and odometer read-
ings.

TIRE ROTATION RECOMMENDATIONS

Do not rotate the tires as the wider rear tires will not fit
on the front of the vehicle.

TIRE PRESSURE MONITOR SYSTEM (TPMS)

Premium System

The Tire Pressure Monitor System (TPMS) uses wireless
technology with wheel rim mounted electronic sensors to
monitor tire pressure levels. Sensors, mounted to each
wheel as part of the valve stem, transmit tire pressure
readings to the Receiver Module.

NOTE:

It is particularly important, for you to check the

tire pressure in all of your tires regularly and to maintain
the proper pressure.

The Tire Pressure Monitor System (TPMS) consists of the
following components:

• Receiver Module
• 4 Tire Pressure Monitoring Sensors
• 3 Trigger Modules (mounted in three of the four wheel

wells)

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• Various Tire Pressure Monitoring System Messages,

which display in the Electronic Vehicle Information
Center (EVIC), and a graphic displaying tire pressures

• Tire Pressure Monitoring Telltale Light

Tire Pressure Monitoring Low Pressure Warnings

The “Tire Pressure Monitoring Telltale Light” will
illuminate in the instrument cluster, and an au-
dible chime will be activated when one or more of

the four active road tire pressures are low. In addition, the
Electronic Vehicle Information Center (EVIC) will display
one or more Low Pressure messages (Left Front, Left
Rear, Right Front, Right Rear) for 3 seconds, and a
graphic display of the pressure value(s) with the low
tire(s) flashing. Refer to “Electronic Vehicle Information
Center (EVIC)” in Section 4 of this manual.

NOTE:

Your system can be set to display pressure units

in PSI, kPa, or BAR.

Should a low tire condition occur on any of the four
active road tire(s), you should stop as soon as possible,
and inflate the low tire(s) that is flashing on the graphic
display to the vehicle’s recommended cold tire pressure.
The system will automatically update, the graphic dis-
play of the pressure value(s) will stop flashing, and the
“Tire Pressure Monitoring Telltale Light” will extinguish

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once the updated tire pressure(s) have been received. The
vehicle may need to be driven for up to 20 minutes above
15 mph (24 km/h) to receive this information.

Check TPM System Message
The “Tire Pressure Monitoring Telltale Light” will flash
on and off for 75 seconds, and remain on solid when a
system fault is detected. The system fault will also sound
a chime. The EVIC will display a “CHECK TPM SYS-
TEM” message for 3 seconds. This text message is then
followed by a graphic display, with “- -“ in place of the
pressure value(s) indicating which Tire Pressure Moni-
toring Sensor(s) is not being received.

NOTE:

Your system can be set to display pressure units

in PSI, kPa, or BAR.

If the ignition key is cycled, this sequence will repeat,
providing the system fault still exists. If the system fault
no longer exists, the “Tire Pressure Monitoring Telltale
Light” will no longer flash, the

⬙CHECK TPM SYSTEM⬙

text message will not be present, and a pressure value
will be displayed instead of dashes. A system fault can
occur by any of the following scenarios:

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Jeep Grand Cherokee SRT8 (2009 year). Instruction - part 20