tire type JEEP WRANGLER 2015 JK / 3.G Owners Manual

maintain correct tire pressure, even if under-inflation has
not reached the level to trigger illumination of the TPMS
low tire pressure telltale.
Your vehicle has also been equipped with a TPMS
malfunction indicator to indicate when the system is not
operating properly. The TPMS malfunction indicator is
combined with the low tire pressure telltale. When the
system detects a malfunction, the telltale will flash for
approximately one minute and then remain continuously
illuminated. This sequence will continue upon subse-
quent vehicle start-ups as long as the malfunction exists.
When the malfunction indicator is illuminated, the sys-
tem may not be able to detect or signal low tire pressure
as intended. TPMS malfunctions may occur for a variety
of reasons, including the installation of replacement or
alternate tires or wheels on the vehicle that prevent the
TPMS from functioning properly. Always check the
TPMS malfunction telltale after replacing one or more
tires or wheels on your vehicle, to ensure that the
replacement or alternate tires and wheels allow the TPMS
to continue to function properly.
CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures and
warning have been established for the tire size
equipped on your vehicle. Undesirable system opera-
tion or sensor damage may result when using re-
placement equipment that is not of the same size,
type, and/or style. Aftermarket wheels can cause
sensor damage. Do not use tire sealant from a can or
balance beads if your vehicle is equipped with a
TPMS, as damage to the sensors may result.
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UNDERSTANDING YOUR INSTRUMENT PANEL 319

!BRAKE SYSTEM.......................468
!ELECTRONIC BRAKE CONTROL SYSTEM . . . .469
▫Anti-Lock Brake System (ABS)............469
▫Traction Control System (TCS)............471
▫Brake Assist System (BAS)...............471
▫Hill Start Assist (HSA).................472
▫Electronic Roll Mitigation (ERM)..........476
▫Electronic Stability Control (ESC)..........477
▫ESC Activation/Malfunction Indicator Light And
ESC OFF Indicator Light................483
▫Trailer Sway Control (TSC)..............484
▫Hill Descent Control (HDC) — If Equipped . . .485
!TIRE SAFETY INFORMATION.............487
▫Tire Markings........................487
▫Tire Identification Number (TIN)...........490
▫Tire Terminology And Definitions..........492
▫Tire Loading And Tire Pressure...........493
!TIRES — GENERAL INFORMATION........498
▫Tire Pressure........................498
▫Tire Inflation Pressures.................500
▫Tire Pressures For High Speed Operation . . . .501
▫Radial Ply Tires......................501
▫Tire Types...........................502
▫Run Flat Tires — If Equipped.............504
▫Spare Tires — If Equipped...............504
▫Tire Spinning........................507
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When operating your vehicle in 4L, the engine speed will
be approximately three times (four times for Rubicon
models) that of the 2H or 4H positions at a given road
speed. Take care not to overspeed the engine.
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 or killed if you leave
the vehicle unattended with the transfer case in the
NEUTRAL (N) position without first fully engaging
(Continued)
WARNING!(Continued)
the parking brake. The transfer case NEUTRAL (N)
position disengages both the front and rear drive
shaft from the powertrain, and will allow the vehicle
to roll, even if the automatic transmission is in PARK
(or manual transmission is in gear). 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
4WD system mode position, see the information below:
2H Position
This range is used for normal street and highway driving
on hard-surfaced roads.
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key to driving in soft sand is using the appropriate tire
pressure, accelerating slowly, avoiding abrupt maneu-
vers and maintaining the vehicle’s momentum. If you are
going to be driving on large soft sandy areas or dunes,
reduce your tire pressure to a minimum of 15 psi (103
kPa) to allow for a greater tire surface area. Reduced tire
pressure will drastically improve your traction and han-
dling while driving on the soft sand, but you must return
the tires to normal air pressure before driving on pave-
ment or other hard surfaces. Be sure you have a way to
reinflate the tires prior to reducing the pressure.
CAUTION!
Reduced tire pressures may cause tire unseating and
total loss of air pressure. To reduce the risk of tire
unseating, while at a reduced tire pressure, reduce
your speed and avoid sharp turns or abrupt maneu-
vers.
Crossing Obstacles (Rocks And Other High
Points)
While driving off-road, you will encounter many types of
terrain. These varying types of terrain bring different
types of obstacles. Before proceeding, review the path
ahead to determine the correct approach and your ability
to safely recover the vehicle if something goes wrong.
Keeping a firm grip on the steering wheel, bring the
vehicle to a complete stop and then inch the vehicle
forward until it makes contact with the object. Apply the
throttle lightly while holding a light brake pressure and
ease the vehicle up and over the object.
WARNING!
Crossing obstacles can cause abrupt steering system
loading which could cause you to loose control of
your vehicle.
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In the event power assist is lost for any reason (for
example, repeated brake applications with the engine
OFF) the brakes will still function. The effort required to
brake the vehicle will be much greater than that required
with the power system operating.
ELECTRONIC BRAKE CONTROL SYSTEM
Your vehicle is equipped with an advanced electronic
brake control system that includes Anti-Lock Brake Sys-
tem (ABS), Traction Control System (TCS), Brake Assist
System (BAS), Hill Start Assist (HSA), Electronic Roll
Mitigation (ERM), Electronic Stability Control (ESC),
Trailer Sway Control (TSC), and Hill Descent Control
(HDC). All of these systems work together to enhance
vehicle stability and control in various driving condi-
tions, and are commonly referred to as ESC.
Anti-Lock Brake System (ABS)
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.
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STARTING AND OPERATING 469

Tire Inflation Pressures
The proper cold tire inflation pressure is listed on the
driver’s side B-Pillar or rear edge of the driver’s side door.
At least once a month:
•Check and adjust tire pressure with a good quality
pocket-type pressure gauge. Do not make a visual
judgement when determining proper inflation. Tires
may look properly inflated even when they are under-
inflated.
•Inspect tires for signs of tire wear or visible damage.
CAUTION!
After inspecting or adjusting the tire pressure, al-
ways reinstall the valve stem cap. 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 three hours, or driven less than 1
mile (1.6 km) after sitting for a minimum of three hours.
The cold tire inflation pressure must not exceed the
maximum inflation pressure 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.
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
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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 and
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 your authorized tire dealer or original
equipment vehicle dealer for recommended safe operat-
ing 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 collision. Do not drive a vehicle loaded to the
maximum capacity at continuous speeds above
75 mph (120 km/h).
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 a collision. Al-
ways use radial ply tires in sets of four. Never
combine them with other types of tires.
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STARTING AND OPERATING 501

Tire Repair
If your tire becomes damaged, it may be repaired if it
meets the following criteria:
•The tire has not been driven on when flat.
•The damage is only on the tread section of your tire
(sidewall damage is not repairable).
•The puncture is no greater than¼#(6 mm).
Consult an authorized tire dealer for tire repairs and
additional information.
Damaged Run Flat tires, or Run Flat tires that have
experienced a loss of pressure should be replaced imme-
diately with another Run Flat tire of identical size and
service description (Load Index and Speed Symbol).
Tire Types
All Season Tires — If Equipped
All Season tires provide traction for all seasons (spring,
summer, fall and winter). Traction levels may vary be-
tween different all season tires. All season tires can be
identified by the M+S, M&S, M/S or MS designation on
the tire sidewall. Use all season tires only in sets of four;
failure to do so may adversely affect the safety and
handling of your vehicle.
Summer Or Three Season Tires — If Equipped
Summer tires provide traction in both wet and dry
conditions, and are not intended to be driven in snow or
on ice. If your vehicle is equipped with summer tires, be
aware these tires are not designed for winter or cold
driving conditions. Install winter tires on your vehicle
when ambient temperatures are less than 40°F (5°C) or if
roads are covered with ice or snow. For more informa-
tion, contact an authorized dealer.
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Summer tires do not contain the all season designation or
mountain/snowflake symbol on the tire sidewall. Use
summer tires only in sets of four; failure to do so may
adversely affect the safety and handling of your vehicle.
WARNING!
Do not use summer tires in snow/ice conditions. You
could lose vehicle control, resulting in severe injury
or death. Driving too fast for conditions also creates
the possibility of loss of vehicle control.
Snow Tires
Some areas of the country require the use of snow tires
during the winter. Snow tires can be identified by a
“mountain/snowflake” symbol on the tire sidewall.
If you need snow tires, select tires
equivalent in size and type to the origi-
nal equipment tires. Use snow tires
only in sets of four; failure to do so
may adversely affect the safety and
handling of your vehicle.
Snow tires generally have lower speed ratings than what
was originally equipped with your vehicle and should
not be operated at sustained speeds over 75 mph
(120 km/h). For speeds above 75 mph (120 km/h) refer to
original equipment or an authorized tire dealer for
recommended safe operating speeds, loading and cold
tire inflation pressures.
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STARTING AND OPERATING 503

While studded tires improve performance on ice, skid
and traction capability on wet or dry surfaces may be
poorer than that of non-studded tires. Some states pro-
hibit studded tires; therefore, local laws should be
checked before using these tire types.
Run Flat Tires — If Equipped
Run Flat tires allow you the capability to drive 50 miles
(80 km) at 50 mph (80 km/h) after a rapid loss of inflation
pressure. This rapid loss of inflation is referred to as the
Run Flat mode. A Run Flat mode occurs when the tire
inflation pressure is of/or below 14 psi (96 kPa). Once a
Run Flat tire reaches the run flat mode it has limited
driving capabilities and needs to be replaced immedi-
ately. A Run Flat tire is not repairable.
It is not recommended driving a vehicle loaded at full
capacity or to tow a trailer while a tire is in the run flat
mode.
See the tire pressure monitoring section for more infor-
mation.
Spare Tires — If Equipped
NOTE:For vehicles equipped with Tire Service Kit
instead of a spare tire, please refer to “Tire Service Kit” in
“What To Do In Emergencies” for further information.
CAUTION!
Because of the reduced ground clearance, do not take
your vehicle through an automatic car wash with a
compact or limited-use temporary spare installed.
Damage to the vehicle may result.
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