2015 JEEP WRANGLER traction control

!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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The transfer case is intended to be driven in the 2H
position for normal street and highway conditions such
as hard-surfaced roads.
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. 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.
Four-Wheel Drive Shift Controls
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TRAC-LOK® REAR AXLE — IF EQUIPPED
The Trac-Lok® rear axle provides a constant driving force
to both rear wheels and reduces wheel spin caused by the
loss of traction at one driving wheel. If traction differs
between the two rear wheels, the differential automati-
cally proportions the usable torque by providing more
torque to the wheel that has traction.
Trac-Lok® is especially helpful during slippery driving
conditions. With both rear wheels on a slippery surface, a
slight application of the accelerator will supply maxi-
mum traction.
WARNING!
On vehicles equipped with a limited-slip differen-
tial, never run the engine with one rear wheel off the
ground. The vehicle may drive through the rear
wheel remaining on the ground and cause you to lose
control of your vehicle.
AXLE LOCK (TRU–LOK®) — RUBICON MODELS
The AXLE LOCK switch is located on the instrument
panel (to the left of the steering column).
Axle Lock Switch
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2. Remove one bolt from the underside of the vehicle.
3. Remove the side step assembly.
The Basics Of Off-Road Driving
You will encounter many types of terrain driving off-
road. You should be familiar with the terrain and area
before proceeding. There are many types of surface
conditions: hard-packed dirt, gravel, rocks, grass, sand,
mud, snow and ice. Every surface has a different effect on
your vehicle’s steering, handling and traction. Control-
ling your vehicle is one of the keys to successful off-road
driving, so always keep a firm grip on the steering wheel
and maintain a good driving posture. Avoid sudden
accelerations, turns or braking. In most cases, there are no
road signs, posted speed limits or signal lights. Therefore,
you will need to use your own good judgment on what is
safe and what is not. When on a trail, you should always
be looking ahead for surface obstacles and changes in
terrain. The key is to plan your future driving route while
remembering what you are currently driving over.
Underside Bolt
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CAUTION!
Never park your vehicle over dry grass or other
combustible materials. The heat from your vehicle
exhaust system could cause a fire.
WARNING!
Always wear your seat belt and firmly tie down
cargo. Unsecured cargo can become projectiles in an
off-road situation.
When To Use 4L (Low) Range
When off-road driving, shift into 4L (Low) for additional
traction and control on slippery or difficult terrain,
ascending or descending steep hills, and to increase low
speed pulling power. This range should be limited to
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.
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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 momen-
tum.
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.
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,
maintain your vehicle’s momentum and do not stop. The
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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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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.
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
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