lock JEEP WRANGLER UNLIMITED 2015 Owner's Manual

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.

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.
4H Position
This range locks the front and rear driveshafts together,
forcing the front and rear wheels to rotate at the same
speed. This range (4H) provides additional traction for
loose, slippery road surfaces and should not be used on
dry pavement.
The “4WD Indicator Light” (located in the instrument
cluster) will illuminate when the transfer case is shifted
into the 4H position.
N (Neutral) Position
This range disengages the front and rear driveshafts from
the powertrain. It is to be used for flat towing behind
another vehicle. Refer to “Recreational Towing” in “Start-
ing and Operating” for further information.
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STARTING AND OPERATING 443

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!
•Never use the PARK position on an automatic
transmission as a substitute for the parking brake.
Always apply the parking brake fully when parked
to guard against vehicle movement and possible
injury or damage.
• When leaving the vehicle, always remove the Key
Fob from the ignition and lock your vehicle.
• Never leave children alone in a vehicle, or with
access to an unlocked vehicle. Allowing children to
be in a vehicle unattended is dangerous for a
number of reasons. A child or others could be
seriously or fatally injured. Children should be
warned not to touch the parking brake, brake pedal
or the shift lever.
(Continued)

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!(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.

A feature of the TCS system, Brake Limited Differential
(BLD), functions similar to a limited slip differential and
controls the wheel spin across a driven axle. If one wheel
on a driven axle is spinning faster than the other, the
system will apply the brake of the spinning wheel. This
will allow more engine torque to be applied to the wheel
that is not spinning. This feature remains active even if
TCS and ESC are in either the “Partial Off” or “Full Off”
modes. Refer to “Electronic Stability Control (ESC)” in
this section for further information.
Brake Assist System (BAS)
The BAS is designed to optimize the vehicle’s braking
capability during emergency braking maneuvers. The
system detects an emergency braking situation by sens-
ing the rate and amount of brake application and then
applies optimum pressure to the brakes. This can help
reduce braking distances. The BAS complements the
anti-lock brake system (ABS). Applying the brakes veryquickly results in the best BAS assistance. To receive the
benefit of the system, you must apply continuous brak-
ing pressure during the stopping sequence. Do not
reduce brake pedal pressure unless braking is no longer
desired. Once the brake pedal is released, the BAS is
deactivated.

Spare Tire Removal
To remove the spare tire from the carrier, remove the tire
cover, if equipped, and remove the lug nuts with the lug
wrench turning them counterclockwise.
NOTE:If you have added aftermarket accessories to the
spare tire mounted carrier, it cannot exceed a gross
weight of 85 lbs (38.5 kg) including the weight of the
spare tire.
Preparations For Jacking
1.Park on a firm, level surface. Avoid ice or slippery areas.
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WHAT TO DO IN EMERGENCIES 565

5. Raise the vehicle by turning the jack screw clockwise.Raise the vehicle only until the tire just clears the
surface and enough clearance is obtained to install the
spare tire. Minimum tire lift provides maximum sta-
bility.

8. Lower the vehicle by turning the jack screw to the left,and remove the jack.
9. Finish tightening the lug nuts. Push down on the wrench while tightening for increased leverage. Alter-
nate nuts until each nut has been tightened twice.
Refer to “Torque Specifications” in this section for
correct lug nut torque.
10. Remove the jack assembly and wheel blocks.
11. Secure the tire, jack, and tools in their proper loca- tions.