2015 JEEP WRANGLER engine

Overdrive Operation
The automatic transmission includes an electronically
controlled Overdrive (fifth gear). The transmission will
automatically shift into Overdrive if the following con-
ditions are present:
•The shift lever is in the DRIVE position.
•Vehicle speed is sufficiently high.
•The driver is not heavily pressing the accelerator.
AUTOSTICK
AutoStick is a driver-interactive transmission feature
providing manual shift control, giving you more control
of the vehicle. AutoStick allows you to maximize engine
braking, eliminate undesirable upshifts and downshifts,
and improve overall vehicle performance.
This system can also provide you with more control
during passing, city driving, cold slippery conditions,
mountain driving, trailer towing, and many other situa-
tions.
Operation
When the shift lever is in the DRIVE position, the
transmission will operate automatically, shifting between
the five available gears. To engage AutoStick, simply tap
the shift lever to the right or left (+/-) while in the DRIVE
position. Tapping (-) to enter AutoStick mode will down-
shift the transmission to the next lower gear, while using
(+) to enter AutoStick mode will retain the current gear.
When AutoStick is active, the current transmission gear is
displayed in the instrument cluster.
In AutoStick mode, the transmission will shift up or
down when (+/-) is manually selected by the driver,
unless an engine lugging or overspeed condition would
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result. It will remain in the selected gear until another
upshift or downshift is chosen, except as described
below.
•The transmission will automatically upshift when nec-
essary to prevent engine over-speed.
•Heavily pressing the accelerator pedal will generate an
automatic downshift (for improved acceleration) when
reasonable.
•The transmission will automatically downshift as the
vehicle slows (to prevent engine lugging) and will
display the current gear.
•The transmission will automatically downshift to first
gear when coming to a stop. After a stop, the driver
should manually upshift (+) the transmission as the
vehicle is accelerated.
•You can start out, from a stop, in first or second gear.
Tapping (+) (at a stop) will allow starting in second
gear. Starting out in second gear can be helpful in
snowy or icy conditions.
•The system will ignore attempts to upshift at too low
of a vehicle speed.
•Avoid using speed control when AutoStick is engaged.
•Transmission shifting will be more noticeable when
AutoStick is engaged.
NOTE:When the transfer case is in the 4L (Low) range,
the transmission will shift automatically (but no higher
than the displayed gear).
To disengage AutoStick mode, hold the shift lever to the
right (+) until#D#is once again displayed in the instru-
ment cluster. You can shift in or out of the AutoStick
mode at any time without taking your foot off the
accelerator pedal.
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WARNING!
Do not downshift for additional engine braking on a
slippery surface. The drive wheels could lose their
grip and the vehicle could skid, causing a collision or
personal injury.
FOUR–WHEEL DRIVE OPERATION (COMMAND-
TRAC I® OR ROCK-TRAC®)
WARNING!
Failure to engage a transfer case position completely
can cause transfer case damage or loss of power and
vehicle control. You could have a collision. Do not
drive the vehicle unless the transfer case is fully
engaged.
Operating Instructions/Precautions
The transfer case provides four mode positions:
•2H (Two-wheel drive high range)
•4H (Four-wheel drive high range)
•N (Neutral)
•4L (Four-wheel drive low range)
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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!
You or others could be injured or killed if you leave
the vehicle unattended with the transfer case in the
NEUTRAL (N) position without first fully engaging
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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.
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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.
4L Position
This range locks the front and rear driveshafts together,
forcing the front and rear wheels to rotate at the same
speed. This range (4L) provides additional traction and
maximum pulling power for loose, slippery road surfaces
only. Do not exceed 25 mph (40 km/h).
CAUTION!
Exceeding 25 mph (40 km/h) while the transfer case is
engaged in 4L may result in an engine overspeed
condition and engine damage.
The “4WD Indicator Light” (located in the instrument
cluster) will illuminate when the transfer case is shifted
into the 4L position.
NOTE:When in 4WD, the “ESC Off Indicator Light” will
display in the instrument cluster.
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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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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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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.
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 or killed.
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