2013 JEEP WRANGLER UNLIMITED tires

In the event that additional traction is required, the
transfer case 4H and 4L positions can be used to lock the
front and rear driveshafts together, forcing the front and
rear wheels to rotate at the same speed. This is accom-
plished by simply moving the shift lever to one of these
positions. 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 components.
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 only the front or rear wheels are spinning
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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extreme situations such as deep snow, mud, steep in-
clines, or sand where additional low speed pulling power
is needed. Vehicle speeds in excess of 25 mph (40 km/h)
should be avoided when in 4L (Low) range.
CAUTION!Do not use 4L (Low) range when operating the
vehicle on dry pavement. Driveline hardware dam-
age can result.
Simultaneous Brake And Throttle Operation
Many off-road driving conditions require the simultane-
ous use of the brake and throttle (two-footed driving).
When climbing rocks, logs, or other stepped objects,
using light brake pressure with light throttle will keep the
vehicle from jerking or lurching. This technique is also
used when you need to stop and restart a vehicle on a
steep incline. Driving In Snow, Mud And Sand
Snow
In heavy snow or for additional control and traction at
slower speeds, shift the transmission into a low gear and
the transfer case into 4L (Low) if necessary. Do not shift to
a lower gear than necessary to maintain headway. Over-
revving the engine can spin the wheels and traction will be
lost. If you start to slow to a stop, try turning your steering
wheel no more than a 1/4 turn quickly back and forth,
while still applying throttle. This will allow the tires to get
a fresh  bite  and help maintain your momentum.
CAUTION!On icy or slippery roads, do not downshift at high
engine RPM or vehicle speeds, because engine brak-
ing may cause skidding and loss of control.
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Mud
Deep mud creates a great deal of suction around the tires
and is very difficult to get through. You should use
second gear (manual transmission), or DRIVE (automatic
transmission), with the transfer case in the 4L (Low)
position to maintain your momentum. If you start to slow
to a stop, try turning your steering wheel no more than a
1/4 turn quickly back and forth for additional traction.
Mud holes pose an increased threat of vehicle damage
and getting stuck. They are normally full of debris from
previous vehicles getting stuck. As a good practice before
entering any mud hole, get out and determine how deep
it is, if there are any hidden obstacles and if the vehicle
can be safely recovered if stuck.
Sand
Soft sand is very difficult to travel through with full tire
pressure. When crossing soft, sandy spots in a trail, main-
tain your vehicle’s momentum and do not stop. The key to driving in soft sand is using the appropriate tire pressure,
accelerating slowly, avoiding abrupt maneuvers and main-
taining 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 drasti-
cally improve your traction and handling while driving on
the soft sand, but you must return the tires to normal air
pressure before driving on pavement or other hard sur-
faces. 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 maneuvers.440 STARTING AND OPERATING

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. Using A Spotter
There are many times where it is hard to see the obstacle
or determine the correct path. Determining the correct
path can be extremely difficult when you are confronting
many obstacles. In these cases have someone guide you
over, through, or around the obstacle. Have the person
stand a safe distance in front of you where they can see
the obstacle, watch your tires and undercarriage, and
guide you through.
Crossing Large Rocks
When approaching large rocks, choose a path which
ensures you drive over the largest of them with your
tires. This will lift your undercarriage over the obstacle.
The tread of the tire is tougher and thicker than the side
wall and is designed to take the abuse. Always look
ahead and make every effort to cross the large rocks with
your tires.
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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 vehi-
cle’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.
WARNING!There is an increased risk of rollover when crossing
an obstacle, at any angle, with steep sides.
Crossing Logs
To cross a log, approach it at a slight angle (approxi-
mately 10 to 15 degrees). This allows one front tire to be
on top of the log while the other just starts to climb the
log. While climbing the log, modulate your brake and
accelerator to avoid spinning the log out from under your
tires. Then ease the vehicle off the log using your brakes.442 STARTING AND OPERATING

CAUTION!Do not attempt to cross a log with a greater diameter
than the running ground clearance or the vehicle will
become high-centered.
Getting High-Centered
If you get hung up or high-centered on an object, get out
of the vehicle and try to determine what the vehicle is
hung up on, where it is contacting the underbody and
what is the best direction to recover the vehicle. Depend-
ing on what you are in contact with, jack the vehicle up
and place a few rocks under the tires so the weight is off
of the high point when you let the vehicle down. You can
also try rocking the vehicle or winching the vehicle off
the object. CAUTION!Winching or rocking the vehicle off hard objects
increases the risk of underbody damage.
Hill Climbing
Hill climbing requires good judgment and a good under-
standing of your abilities and your vehicle’s limitations.
Hills can cause serious problems. Some are just too steep
to climb and should not be attempted. You should always
feel confident with the vehicle and your abilities. You
should always climb hills straight up and down. Never
attempt to climb a hill on an angle.
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Before Climbing A Steep Hill
As you approach a hill, consider its grade or steepness.
Determine if it is too steep. Look to see what the traction
is on the hill side trail. Is the trail straight up and down?
What is on top and the other side? Are there ruts, rocks,
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 accelerator
and maintain headway by turning the steering wheel no
more than a 1/4 turn quickly back and forth. This will
provide a fresh  bite  into 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.
WARNING!Never attempt to climb a hill at an angle or turn
around on a steep grade. Driving across an incline
increases the risk of a rollover, which may result in
severe injury.444 STARTING AND OPERATING

Driving Downhill
Before driving down a steep hill, you need to determine
if it is too steep for a safe descent. What is the surface
traction? Is the grade too steep to maintain a slow,
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.
WARNING!Do not descend a steep grade in NEUTRAL. Use
vehicle brakes in conjunction with engine braking.
Descending a grade too fast could cause you to lose
control and be seriously injured. Driving Across An Incline
If at all possible, avoid driving across an incline. If it is
necessary, know your vehicle’s abilities. Driving across
an incline places more weight on the downhill wheels,
which increases the possibilities of a downhill slide or
rollover. Make sure the surface has good traction with
firm and stable soils. If possible, transverse the incline at
an angle heading slightly up or down.
WARNING!Driving across an incline increases the risk of a
rollover , which may result in severe injury.
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