tires JEEP WRANGLER UNLIMITED 2015 Owners Manual
[x] Cancel search | Manufacturer: JEEP, Model Year: 2015, Model line: WRANGLER UNLIMITED, Model: JEEP WRANGLER UNLIMITED 2015Pages: 695, PDF Size: 4.85 MB
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rear wheels to rotate at the same speed. The 4H and 4L
positions are intended for loose, slippery road surfaces
only and not intended for normal driving. Driving in the
4H and 4L positions on hard-surfaced roads will cause
increased tire wear and damage to the driveline compo-
nents. Refer to “Shifting Procedures” in this section for
further information on shifting into 4H or 4L.
The “4WD Indicator Light” (located in the instrument
cluster) alerts the driver that the vehicle is in four-wheel
drive, and the front and rear driveshafts are locked
together. The light will illuminate when the transfer case
is shifted into the 4H position.
NOTE:Do not attempt to shift when only the front or
rear wheels are spinning. The transfer case is not
equipped with a synchronizer, and the front and rear
driveshaft speeds must be equal for a shift to take place.
Shifting while the front or rear wheels are spinning at
different speeds can cause damage to the transfer case. 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.
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CAUTION!
•Never attempt to straddle a rock that is large
enough to strike your axles or undercarriage.
• Never attempt to drive over a rock which is large
enough to contact the door sills.
Crossing A Ravine, Gully, Ditch, Washout Or Rut
When crossing a ravine, gully, ditch, washout or a large
rut, the angled approach is the key to maintaining your
vehicle’s mobility. Approach these obstacles at a 45-
degree angle and let each tire go through the obstacle
independently. You need to use caution when crossing
large obstacles with steep sides. Do not attempt to cross
any large obstacle with steep sides at an angle great
enough to put the vehicle at risk of a rollover. If you get
caught in a rut, dig a small trench to the right or left at a
45-degree angle ahead of the front tires. Use the removed
dirt to fill the rut ahead of the turnout you just created. You should now be able to drive out following the trench
you just created at a 45-degree angle.
Page 459 of 695

branches or other obstacles on the path? Can you safely
recover the vehicle if something goes wrong? If every-
thing looks good and you feel confident, shift the trans-
mission into a lower gear with 4L (Low) engaged, and
proceed with caution, maintaining your momentum as
you climb the hill.
Driving Up Hill
Once you have determined your ability to proceed and
have shifted into the appropriate gear, line your vehicle
up for the straightest possible run. Accelerate with an
easy constant throttle and apply more power as you start
up the hill. Do not race forward into a steep grade; the
abrupt change of grade could cause you to lose control. If
the front end begins to bounce, ease off the throttle
slightly to bring all four tires back on the ground. As you
approach the crest of the hill, ease off the throttle and
slowly proceed over the top. If the wheels start to slip as
you approach the crest of a hill, ease off the acceleratorand maintain headway by turning the steering wheel no
more than a 1/4 turn quickly back and forth. This will
provide a fresh
biteinto the surface and will usually
provide enough traction to complete the climb. If you do
not make it to the top, place the vehicle in REVERSE and
back straight down the grade using engine resistance
along with the vehicle brakes.
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controlled descent? Are there obstacles? Is it a straight
descent? Is there plenty of distance at the base of the hill
to regain control if the vehicle descends to fast? If you feel
confident in your ability to proceed, then make sure you
are in 4L (Low) and proceed with caution. Allow engine
braking to control the descent and apply your brakes, if
necessary, but do not allow the tires to lock.
Page 463 of 695

CAUTION!
Muddy waters can reduce the cooling system effec-
tiveness by depositing debris onto the radiator.
Crossing Ditches, Streams, Shallow Rivers Or
Other Flowing Water
Flowing water can be extremely dangerous. Never at-
tempt to cross a fast running stream or river even in
shallow water. Fast moving water can easily push your
vehicle downstream, sweeping it out of control. Even in
very shallow water, a high current can still wash the dirt
out from around your tires putting you and your vehicle
in jeopardy. There is still a high risk of personal injury
and vehicle damage with slower water currents in depths
greater than the vehicle’s running ground clearance. You
should never attempt to cross flowing water which is
deeper than the vehicle’s running ground clearance. Eventhe slowest current can push the heaviest vehicle down-
stream and out of control if the water is deep enough to
push on the large surface area of the vehicle’s body.
Before you proceed, determine the speed of the current,
the water’s depth, approach angle, bottom condition and
if there are any obstacles. Then cross at an angle heading
slightly upstream using the low and slow technique.
Page 464 of 695

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. •
After extended operation in mud, sand, water, or
similar dirty conditions, have the radiator, fan, brake
rotors, wheels, brake linings, and axle yokes inspected
and cleaned as soon as possible.
Page 470 of 695

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.
Page 471 of 695

WARNING!(Continued)
•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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•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), 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.
Page 499 of 695

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. Four primary areas
are affected by improper tire pressure:
•Safety and Vehicle Stability
• Economy
• Tread Wear •
Ride Comfort
Safety