tire size JEEP GRAND CHEROKEE 2004 WK / 3.G Owners Manual

Proper operation of four wheel drive vehicles depends on
tires of equal size, type, and circumference on each
wheel. Any difference will adversely affect shifting and
cause damage to the transfer case.
Because four wheel drive provides improved traction,
there is a tendency to exceed safe turning and stopping
speeds. Do not go faster than road conditions permit.
WARNING!
You or others could be injured if you leave the
vehicle unattended with the transfer case in the N
(Neutral) position without first fully engaging the
parking brake. The transfer case N (Neutral) position
disengages both the front and rear driveshafts from
the powertrain and will allow the vehicle to move
regardless of the transmission position. The parking
brake should always be applied when the driver is
not in the vehicle.
Shift Positions
For additional information on the appropriate use of each
transfer case mode position, see the information below:
2WD
Rear Wheel Drive High Range Ð Normal street and
highway driving. Dry hard surfaced roads.
4 PART TIME
Part Time 4 Wheel Drive High Range Ð Locks the
transfer case inter-axle differential. Forces the front and
rear wheels to rotate at the same speed. Additional
traction for loose, slippery road surfaces only.
4 FULL TIME
Full Time 4 Wheel Drive High Range Ð Employs inter-
axle differential. Allows front and rear wheels to rotate at
different speeds. All roads surfaces.
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5 km/h). Avoid attempting to engage or disengage 4LO
with the vehicle moving faster than 2 to 3 mph (3 to 5
km/h).
Quadra-Trac IITOperating
Instructions/Precautions Ð If Equipped
The Quadra-Trac IIttransfer case is fully automatic in the
normal driving 4 ALL TIME mode. The Quadra-Trac IIt
transfer case provides three mode positions Ð four wheel
drive high range, neutral, and four wheel drive low
range.
This transfer case is fully automatic in the 4 ALL TIME
mode. The 4 ALL TIME mode transmits torque to the rear
axle during normal driving, similar to a rear wheel drive
vehicle. When speed difference is increased between the
front and rear driveshafts the majority of engine torque
can be transmitted to the front driveshaft.
When additional traction is required, the 4LO position
can be used to lock the front and rear driveshafts togetherand force the front and rear wheels to rotate at the same
speed. The 4LO position is intended for loose, slippery
road surfaces only. Driving in the 4LO position on dry
hard surfaced roads may cause increased tire wear and
damage to driveline components.
When operating your vehicle in 4LO, the engine speed is
approximately three times that of the 4 ALL TIME
position at a given road speed. Take care not to overspeed
the engine and do not exceed 25 mph (40 km/h).
Proper operation of four wheel drive vehicles depends on
tires of equal size, type, and circumference on each
wheel. Any difference will adversely affect shifting and
cause damage to the transfer case.
Because four wheel drive provides improved traction,
there is a tendency to exceed safe turning and stopping
speeds. Do not go faster than road conditions permit.
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ANTI-LOCK BRAKE SYSTEM
The Anti-Lock Brake System (ABS) is designed to aid the
driver in maintaining vehicle control under adverse
braking conditions. The system operates with a separate
computer to modulate hydraulic pressure to prevent
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 Anti-Lock Brake System 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 Anti-Lock Brake System 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.
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TIRE SAFETY INFORMATION
Tire Markings
NOTE:
²P(Passenger)-Metric tire sizing is based on U.S. design
standards. P-Metric tires have the letter ªPº molded
into the sidewall preceding the size designation. Ex-
ample: P215/65R15 95H.
²European 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 letter9P9is absent from this tire
size designation. Example: 215/65R15 96H
²LT(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 ªLTº that are molded into the sidewall preced-
ing the size designation. Example: LT235/85R16.
²Temporary Spare tires are high pressure compact
spares designed for temporary emergency use only.
Tires designed to this standard have the letter ªTº
molded into the sidewall preceding the size designa-
tion. Example: T145/80D18 103M.
²High Flotation tire sizing is based on U.S. design
standards and 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
T= Temporary Spare tire
31= Overall Diameter in Inches (in)
215= Section Width in Milimeters (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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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 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
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:Some vehicles have a ªTire and Loading Infor-
mationº placard located on 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.
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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 the Vehicle Loading section 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, see the
Vehicle Loading 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. 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 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.
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WARNING!
²Do not use a tire, wheel size or rating other than that
specified for your vehicle. Some combinations of
unapproved tires and wheels may change suspen-
sion dimensions and performance characteristics,
resulting in changes to steering, handling, and brak-
ing of your vehicle. This can cause unpredictable
handling and stress to steering and suspension com-
ponents. 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.
²Never use a tire smaller than the minimum tire size
listed on your vehicle's tire label. Using a smaller tire
could result in tire overloading and failure. You
could lose control and have an accident.
²Failure to equip your vehicle with tires having
adequate speed capability can result in sudden tire
failure and loss of vehicle control.
²Overloading your tires is dangerous. Overloading
can cause tire failure. Use tires of the recommended
load capacity for your vehicle - never overload them.
CAUTION!
Replacing original tires with tires of a different size
may result in false speedometer and odometer read-
ings. Check with your dealer before replacing tires
with a different size.
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Alignment and Balance
The suspension components of your vehicle should be
inspected and aligned when needed, to obtain maximum
tire tread life.
Poor suspension alignment may result in:
²reduced tread life;
²uneven tire wear, such as feathering and one-sided
wear;
²vehicle pull to the right or to the left.
Tires may also cause the vehicle to pull left or right.
Alignment will not correct this problem. See your dealer
for proper diagnosis of the problem.
Improper alignment will not normally cause vehicle
vibration, which may be a result of tire and wheel
out-of-balance. Proper balancing will reduce vibration
and avoid tire cupping and spotty wear.
TIRE PRESSURE MONITOR SYSTEM Ð IF
EQUIPPED
The Tire Pressure Monitor System (TPM) monitors the
pressure in all 4 road tires and the full size spare (5 Tire
TPM System Only). The TPM system uses wireless
technology to monitor tire pressure levels. Sensors,
mounted to each wheel as part of the valve stem, transmit
tire pressure readings to a receiver located in the over-
head console. The tire pressure status is shown in the
Electronic Vehicle Information Center (EVIC) display.
Refer to ªOverhead Consoleº in Section 3 for more
information. The TPM system functions even when the
EVIC is not set on the tire pressure display screen.
The TPM system informs you of a low or high tire
pressure condition. If this occurs, correct your tire infla-
tion pressure as soon as possible, and inspect all of your
tires. Be sure to use a high quality gauge when adjusting
pressure. The TPM system is designed to monitor your
tire pressure but will not function as a tire pressure
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