2015 JEEP GRAND CHEROKEE tires

Avoid abrupt downshifts on icy or slippery roads, be-
cause engine braking may cause skidding and loss of
control.
Hill Climbing
NOTE:Before attempting to climb a hill, determine the
conditions at the crest and/or on the other side.
Before climbing a steep hill,shift the transmission to a
lower gear and shift the transfer case to 4WD LOW. Use
first gear and 4WD LOW for very steep hills.
If you stall or begin to lose forward motionwhile
climbing a steep hill, allow your vehicle to come to a stop
and immediately apply the brakes. Restart the engine,
and shift into REVERSE. Back slowly down the hill,
allowing the compression braking of the engine to help
regulate your speed. If the brakes are required to control
vehicle speed, apply them lightly and avoid locking or
skidding the tires.
WARNING!
If the engine stalls, you lose forward motion, or
cannot make it to the top of a steep hill or grade,
never attempt to turn around. To do so may result in
tipping and rolling the vehicle. Always back care-
fully straight down a hill in REVERSE gear. Never
back down a hill in NEUTRAL using only the brake.
Remember, never drive diagonally across a hill always
drive straight up or down.
If the wheels start to slip as you approach the crest of a
hill, ease off the accelerator and maintain forward motion
by turning the front wheels slowly. This may provide a
fresh “bite” into the surface and will usually provide
traction to complete the climb.
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Traction Downhill
When descending mountains or hills, use Hill Descent or
Selec-Speed Control to avoid repeated heavy braking.
If not equipped with Hill Descent or Selec-Speed Control
use the following procedure:
Shift the transmission into a low gear, and the transfer
case into 4WD LOW range. Let the vehicle go slowly
down the hill with all four wheels turning against engine
compression drag. This will permit you to control the
vehicle speed and direction.
When descending mountains or hills, repeated braking
can cause brake fade with loss of braking control. Avoid
repeated heavy braking by downshifting the transmis-
sion whenever possible.
After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road, it is
always a good idea to check for damage. That way you
can get any problems taken care of right away and have
your vehicle ready when you need it.
•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
•Inspect the radiator for mud and debris and clean as
required.
•Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
•Check for accumulations of plants or brush. These
things could be a fire hazard. They might hide damage
to fuel lines, brake hoses, axle pinion seals, and
propeller shafts.
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In the event power assist is lost for any reason (i.e.,
repeated brake applications with the engine off) the
brakes will still function. However, 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 the Anti-Lock Brake
System (ABS), Traction Control System (TCS), Brake
Assist System (BAS), Electronic Roll Mitigation (ERM),
and Electronic Stability Control (ESC). All five of these
systems work together to enhance vehicle stability and
control in various driving conditions.
Also, your vehicle may be equipped with Trailer Sway
Control (TSC), Hill Start Assist (HSA), Ready Alert
Braking (RAB), Rain Brake Support (RBS) and, if it has
four-wheel drive with the MP 3023 two-speed transfer
case, Hill Descent Control (HDC), Selec Speed Control
(SSC).
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.
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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 for any reason your
foot is on the brake when the vehicle reaches 12 mph
(20 km/h), this check will be delayed until 25 mph
(40 km/h).
The Anti-Lock Brake System pump motor runs during
the self-test, and during an ABS stop, to provide the
regulated hydraulic pressure. The motor pump makes a
low humming noise during operation; this is normal.
WARNING!
•Pumping of the Anti-Lock Brakes will diminish
their effectiveness and may lead to a collision.
Pumping makes the stopping distance longer. Just
press firmly on your brake pedal when you need to
slow down or stop.
•The Anti-Lock Brake System (ABS) cannot prevent
the natural laws of physics from acting on the
vehicle, nor can they increase braking or steering
efficiency beyond that afforded by the condition of
the vehicle brakes and tires or the traction afforded.
•The ABS cannot prevent collisions, including those
resulting from excessive speed in turns, following
another vehicle too closely, or hydroplaning.
•The capabilities of an ABS-equipped vehicle must
never be exploited in a reckless or dangerous
manner which could jeopardize the user’s safety or
the safety of others.
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WARNING!
Many factors, such as vehicle loading, road condi-
tions, and driving conditions, influence the chance
that wheel lift or rollover may occur. ERM cannot
prevent all wheel lift or rollovers, especially those
that involve leaving the roadway or striking objects
or other vehicles. The capabilities of an ERM-
equipped vehicle must never be exploited in a reck-
less or dangerous manner, which could jeopardize
the user’s safety or the safety of others.
Electronic Stability Control (ESC)
This system enhances directional control and stability of
the vehicle under various driving conditions. ESC cor-
rects for oversteering or understeering of the vehicle by
applying the brake of the appropriate wheel to assist in
counteracting the oversteer or understeer condition. En-
gine power may also be reduced to help the vehicle
maintain the desired path.
ESC uses sensors in the vehicle to determine the vehicle
path intended by the driver and compares it to the actual
path of the vehicle. When the actual path does not match
the intended path, ESC applies the brake of the appro-
priate wheel to assist in counteracting the oversteer or
understeer condition.
•Oversteer - when the vehicle is turning more than
appropriate for the steering wheel position.
•Understeer - when the vehicle is turning less than
appropriate for the steering wheel position.
The “ESC Activation/Malfunction Indicator Light” lo-
cated in the instrument cluster will start to flash as soon
as the tires lose traction and the ESC system becomes
active. The “ESC Activation/Malfunction Indicator
Light” also flashes when the TCS is active. If the “ESC
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vehicle has been driven several miles (kilometers) at
speeds greater than 30 mph (48 km/h), see your autho-
rized dealer as soon as possible to have the problem
diagnosed and corrected.
The “ESC Activation/Malfunction Indicator Light” (lo-
cated in the instrument cluster) starts to flash as soon as
the tires lose traction and the ESC system becomes active.
The “ESC Activation/Malfunction Indicator Light” also
flashes when TCS is active. If the “ESC Activation/
Malfunction Indicator Light” begins to flash during ac-
celeration, ease up on the accelerator and apply as little
throttle as possible. Be sure to adapt your speed and
driving to the prevailing road conditions.
NOTE:
•The “ESC Off Indicator Light” and the “ESC
Activation/Malfunction Indicator Light” come on mo-
mentarily each time the ignition switch is turned to the
ON/RUN position.
•Each time the ignition is cycled to the ON/RUN
position, the ESC system will be ON even if it was
cycled off previously, except for when the vehicle is
started while in 4L Range.
•The ESC system will make buzzing or clicking sounds
when it is active. This is normal; the sounds will stop
when ESC becomes inactive following the maneuver
that caused the ESC activation.
The “ESC OFF Indicator Light” indicates the
Electronic Stability Control (ESC) is partially
off or full off.
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TIRE SAFETY INFORMATION
Tire Markings
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 letter#P#is 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.
1—U.S.DOTSafetyStandardsCode (TIN)4—MaximumLoad
2—SizeDesignation 5—MaximumPressure3 — Service Description 6 — Treadwear, Traction andTemperature Grades
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•Temporary spare tires are designed for temporary
emergency use only. Temporary high pressure com-
pact spare tires have the letter “T” or “S” molded into
the sidewall preceding the size designation. Example:
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.
Tire Sizing Chart
EXAMPLE:
Example Size Designation: P215/65R15XL 95H, 215/65R15 96H, LT235/85R16C, T145/80D18 103M, 31x10.5 R15 LT
P= Passenger car tire size based on U.S. design standards, or
'....blank....'= Passenger car tire based on European design standards, or
LT= Light truck tire based on U.S. design standards, or
TorS= Temporary spare tire or
31= Overall diameter in inches (in)
215, 235, 145= Section width in millimeters (mm)
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