2021 JEEP WRANGLER UNLIMITED Owner handbook (in English)

143
(Continued)
ENGINE BREAK-IN
RECOMMENDATIONS
A long break-in period is not required for the
engine and drivetrain (transmission and axle)
in your vehicle.
Drive moderately during the first 300 miles
(500 km). After the initial 60 miles
(100 km), speeds up to 50 or 55 mph (80 or
90 km/h) are desirable.
While cruising, brief full-throttle accelera-
tion within the limits of local traffic laws
contributes to a good break-in. Wide-open
throttle acceleration in low gear can be detri -
mental and should be avoided.
The engine oil installed in the engine at the
factory is a high-quality energy conserving
type lubricant. Oil changes should be consis -
tent with anticipated climate conditions
under which vehicle operations will occur.
For the recommended viscosity and quality
grades, refer to “Fluids And Lubricants” in
“Technical Specifications”. NOTE:
A new engine may consume some oil during
its first few thousand miles (kilometers) of
operation. This should be considered a
normal part of the break-in and not inter
-
preted as a problem.
AUTOMATIC
TRANSMISSION
NOTE:
You must press and hold the brake pedal
while shifting out of PARK. CAUTION!
Never use Non-Detergent Oil or Straight
Mineral Oil in the engine or damage may
result.
CAUTION!
Shift into or out of PARK or REVERSE
only after the vehicle has come to a
complete stop.
Do not shift between PARK, REVERSE,
NEUTRAL, or DRIVE when the engine is
above idle speed.
Before shifting into any gear, make sure
your foot is firmly pressing the brake
pedal.
WARNING!
Never use the PARK position as a substi -
tute for the parking brake. Always apply
the parking brake fully when exiting the
vehicle to guard against vehicle move-
ment and possible injury or damage.
Your vehicle could move and injure you
and others if it is not in PARK. Check by
trying to move the transmission gear
selector out of PARK with the brake
pedal released. Make sure the transmis-
sion is in PARK before exiting the
vehicle.
The transmission may not engage PARK
if the vehicle is moving. Always bring the
vehicle to a complete stop before
shifting to PARK, and verify that the
transmission gear position indicator
solidly indicates PARK (P) without
blinking. Ensure that the vehicle is
completely stopped, and the PARK posi -
tion is properly indicated, before exiting
the vehicle.
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STARTING AND OPERATING
144
(Continued)
Ignition Park Interlock
This vehicle is equipped with an Ignition
Park Interlock which requires the transmis-
sion to be in PARK before the ignition can be
turned to the OFF mode. This helps the
driver avoid inadvertently leaving the vehicle
without placing the transmission in PARK.
This system also locks the transmission in
PARK whenever the ignition is in the OFF
mode. NOTE:
The transmission is NOT locked in PARK
when the ignition is in the ACC mode (even
though the engine will be off). Ensure that
the transmission is in PARK, and the ignition
is
OFF (not in ACC mode) before exiting the
vehicle.
Brake/Transmission Shift Interlock
System
This vehicle is equipped with a Brake Trans -
mission Shift Interlock system (BTSI) that
holds the transmission gear selector in PARK
unless the brakes are applied. To shift the
transmission out of PARK, the engine must
be running and the brake pedal must be
pressed. The brake pedal must also be
pressed to shift from NEUTRAL into DRIVE
or REVERSE when the vehicle is stopped or
moving at low speeds.
It is dangerous to shift out of PARK or
NEUTRAL if the engine speed is higher
than idle speed. If your foot is not firmly
pressing the brake pedal, the vehicle
could accelerate quickly forward or in
reverse. You could lose control of the
vehicle and hit someone or something.
Only shift into gear when the engine is
idling normally and your foot is firmly
pressing the brake pedal.
Unintended movement of a vehicle could
injure those in or near the vehicle. As
with all vehicles, you should never exit a
vehicle while the engine is running.
Before exiting a vehicle, always come to
a complete stop, then apply the parking
brake, shift the transmission into PARK,
and turn the ignition OFF. When the igni -
tion is in the OFF mode, the transmis-
sion is locked in PARK, securing the
vehicle against unwanted movement.
When exiting the vehicle, always make
sure the ignition is in the OFF mode,
remove the key fob from the vehicle, and
lock the vehicle.
WARNING! (Continued)
Never leave children alone in a vehicle,
or with access to an unlocked vehicle.
Allowing children to be in a vehicle unat -
tended is dangerous for a number of
reasons. A child or others could be seri -
ously or fatally injured. Children should
be warned not to touch the parking
brake, brake pedal or the transmission
gear selector.
Do not leave the key fob in or near the
vehicle (or in a location accessible to
children), and do not leave the ignition
in the ACC or ON/RUN mode. A child
could operate power windows, other
controls, or move the vehicle.
WARNING! (Continued)
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145
Eight–Speed Automatic Transmission
Your vehicle is equipped with a fuel efficient
8 speed transmission. The gear selector is
located in the center console.Transmission Gear Selector
The transmission gear selector provides
PARK, REVERSE, NEUTRAL, DRIVE and
MANUAL (AutoStick) shift positions. Manual
shifts can be made using the AutoStick shift
control. Toggling the gear selector forward (-)
or rearward (+) while in the MANUAL (Auto -
Stick) position (beside the DRIVE position)
will manually select the transmission gear,
and will display the current gear in the
instrument cluster. Refer to "AutoStick" in
this section for further information. NOTE:
If the gear selector cannot be moved to the
PARK, REVERSE, or NEUTRAL position
(when pushed forward), it is probably in the
AutoStick (+/-) position (beside the DRIVE
position). In AutoStick mode, the transmis
-
sion gear (1, 2, 3, etc.) is displayed in the
instrument cluster. Move the gear selector to
the right (into the DRIVE [D] position) for
access to PARK, REVERSE, and NEUTRAL.
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, elim -
inate undesirable upshifts and downshifts,
and improve overall vehicle performance.
This system can also provide you with more
control during passing, city driving, cold slip -
pery conditions, mountain driving, trailer
towing, and many other situations. Operation

To activate AutoStick mode, move the gear
selector into the MANUAL (M) position (beside
the DRIVE position). The current transmission
gear will be displayed in the instrument cluster.
In AutoStick mode, you can use the gear
selector (in the MANUAL position) to manually
shift the transmission. Tapping the gear
selector forward (-) while in the MANUAL (M)
position will downshift the transmission to the
next lower gear. Tapping the selector rearward
(+) will command an upshift.

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 result.
It will remain in the selected gear until
another upshift or downshift is chosen,
except as described below.
The transmission will automatically down
-
shift as the vehicle slows (to prevent
engine lugging) and will display the
current gear.
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STARTING AND OPERATING
146
The transmission will automatically down-
shift 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 (or THIRD gear, in 4L
range). Tapping (+) (at a stop) will allow
starting in SECOND gear. Starting out in
SECOND or THIRD gear can be helpful in
snowy or icy conditions.
If a requested downshift would cause the
engine to over-speed, that shift will not
occur.
The system will ignore attempts to upshift
at too low of a vehicle speed.
Holding the gear selector in the (-) posi -
tion will downshift the transmission to the
lowest gear possible at the current speed.
Transmission shifting will be more notice-
able when AutoStick is enabled.
The system may revert to automatic shift
mode if a fault or overheat condition is
detected. NOTE:
When Hill Descent Control is enabled, Auto
-
Stick is not active.
To disengage AutoStick mode, return the
gear selector to the DRIVE position. You can
shift in or out of the AutoStick position at any
time without taking your foot off the acceler -
ator pedal.
FOUR–WHEEL DRIVE
OPERATION
Four-Position Transfer Case
Four-Wheel Drive Gear Selector
The transfer case provides four mode posi -
tions:
2H (Two-Wheel Drive High Range)
4H (Four-Wheel Drive High Range)
N (Neutral)
4L (Four-Wheel Drive Low Range)
For additional information on the appropriate
use of each transfer case mode position, see
the information below:
2H
Two-Wheel Drive High Range — This range is
for normal street and highway driving on dry,
hard surfaced roads.
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.
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.
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147
4H
Four-Wheel Drive High Range — This range
maximizes torque to the front driveshaft,
forcing the front and rear wheels to rotate at
the same speed. This range provides addi-
tional traction for loose, slippery road
surfaces only.
NEUTRAL (N)
Neutral — This range disengages both the
front and rear driveshafts from the power -
train. To be used for flat towing behind
another vehicle.
Refer to “Recreational Towing” in this
chapter for further information. 4L
Four-Wheel Drive Low Range — This range
provides low speed four-wheel drive. It maxi
-
mizes torque to the front driveshaft, forcing
the front and rear wheels to rotate at the
same speed. This range provides additional
traction and maximum pulling power for
loose, slippery road surfaces only. Do not
exceed 25 mph (40 km/h).
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 posi -
tions 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 drive -
line components. Refer to “Shifting Proce -
dures” in this section for further information
on shifting into 4H or 4L. 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.
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.
Shifting Procedures
2H To 4H Or 4H To 2H
Shifting between 2H and 4H can be made
with the vehicle stopped or in motion. The
preferred shifting speed would be 0 to
45 mph (72 km/h). With the vehicle in
motion, the transfer case will engage/disen
-
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 the parking
brake. The transfer case NEUTRAL (N)
position disengages both the front and rear
driveshafts from the powertrain, and will
allow the vehicle to roll, even if the
automatic transmission is in PARK. The
parking brake should always be applied
when the driver is not in the vehicle.
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STARTING AND OPERATING
148
gage faster if you momentarily release the
accelerator pedal after completing the shift.
Do not accelerate while shifting the transfer
case. Apply a constant force when shifting
the transfer case lever.
NOTE:

Do not attempt to make a shift while only the
front or rear wheels are spinning. The front
and rear driveshaft speeds must be equal for
the shift to take place. Shifting while only
the front or rear wheels are spinning can
cause damage to the transfer case.

Delayed shifts out of four-wheel drive may
be experienced due to uneven tire wear,
low or uneven tire pressures, excessive
vehicle loading, or cold temperatures.
Shifting effort will increase with speed,
this is normal.
During cold weather, you may experience
increased effort in shifting until the transfer
case fluid warms up. This is normal.
4H To 4L Or 4L To 4H
With the vehicle rolling at 2 to 3 mph (3 to
5 km/h), shift the transmission into
NEUTRAL (N). While the vehicle is coasting
at 2 to 3 mph (3 to 5 km/h), shift the
transfer case lever firmly to the desired posi -
tion. Do not pause with the transfer case in
N (Neutral). Once the shift is completed,
place the transmission into DRIVE.
NOTE:
Shifting into or out of 4L is possible with the
vehicle completely stopped; however, diffi -
culty may occur due to the mating teeth not
being properly aligned. Several attempts may
be required for clutch teeth alignment and
shift completion to occur. The preferred
method is with the vehicle rolling at 2 to
3 mph (3 to 5 km/h). Avoid attempting to
engage or disengage 4L with the vehicle
moving faster than 2 to 3 mph (3 to 5 km/h).
Five-Position Transfer Case
Four-Wheel Drive Gear Selector
The transfer case provides five mode posi -
tions:
2H (Two-Wheel Drive High Range)
4H AUTO (Four-Wheel Drive Auto High
Range)
4H PT (Four-Wheel Drive Part Time High
Range)
N (Neutral)
4L (Four-Wheel Drive Low Range)
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.

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149
For additional information on the appropriate
use of each transfer case mode position, see
the information below:
2H
Two-Wheel Drive High Range — This range is
for normal street and highway driving on dry,
hard surfaced roads.
4H AUTO
Four-Wheel Drive Auto High Range — This
range sends power to the front wheels. The
four-wheel drive system will be automatically
engaged when the vehicle senses a loss of
traction. Additional traction for varying road
conditions.
4H PT
Four-Wheel Drive Part Time High Range —
This range maximizes torque to the front
driveshaft, forcing the front and rear wheels
to rotate at the same speed. This range
provides additional traction for loose, slip-
pery road surfaces only. NEUTRAL (N)
Neutral — This range disengages both the
front and rear driveshafts from the power
-
train. To be used for flat towing behind
another vehicle.
Refer to “Recreational Towing” in this
chapter for further information. 4L
Four-Wheel Drive Low Range — This range
provides low speed four-wheel drive. It maxi
-
mizes torque to the front driveshaft, forcing
the front and rear wheels to rotate at the
same speed. This range provides additional
traction and maximum pulling power for
loose, slippery road surfaces only. Do not
exceed 25 mph (40 km/h).
This transfer case is designed to be driven in
the 2H mode or 4H AUTO mode for normal
street and highway conditions on dry hard
surfaced roads. Driving the vehicle in 2H will
have greater fuel economy benefits as the
front axle is not engaged in 2H.
For variable driving conditions, the 4H AUTO
mode can be used. In this mode, the front
axle is engaged, but the vehicle's power is
sent to the rear wheels. Four-wheel drive will
be automatically engaged when the vehicle
senses a loss of traction. Because the front
axle is engaged, this mode will result in lower
fuel economy than the 2H mode.
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 the parking
brake. The transfer case NEUTRAL (N)
position disengages both the front and rear
driveshafts from the powertrain, and will
allow the vehicle to roll, even if the
automatic transmission is in PARK. The
parking brake should always be applied
when the driver is not in the vehicle.
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STARTING AND OPERATING
150
In the event that additional traction is
required, the transfer case 4H and 4L posi-
tions 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 drive -
line components. Refer to “Shifting Proce -
dures” in this section for further information
on shifting into 4H or 4L.
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.
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.
Shifting Procedures
2H To 4H Auto Or 4H Auto To 2H
Shifting between 2H and 4H Auto can be
made with the vehicle stopped or in motion.
The preferred shifting speed would be 0 to
45 mph (72 km/h). With the vehicle in
motion, the transfer case will engage/disen
-
gage faster if you momentarily release the
accelerator pedal after completing the shift.
Do not accelerate while shifting the transfer
case. Apply a constant force when shifting
the transfer case lever.
2H/4H Auto To 4H Part Time Or 4H Part Time To
2H/4H Auto
Shifting between 2H/4H AUTO to 4H PART
TIME can be made with the vehicle stopped
or in motion. The preferred shifting speed
would be 0 to 45 mph (72 km/h). With the
vehicle in motion, the transfer case will
engage/disengage faster if you momentarily
release the accelerator pedal after
completing the shift. Do not accelerate while shifting the transfer case. Apply a constant
force when shifting the transfer case lever.
NOTE:
Do not attempt to make a shift while only
the front or rear wheels are spinning. The
front and rear driveshaft speeds must be
equal for the shift to take place. Shifting
while only the front or rear wheels are
spinning can cause damage to the transfer
case.
Delayed shifts out of four-wheel drive may
be experienced due to uneven tire wear,
low or uneven tire pressures, excessive
vehicle loading, or cold temperatures.
Shifting effort will increase with speed,
this is normal.
During cold weather, you may experience
increased effort in shifting until the transfer
case fluid warms up. This is normal.
4H Part Time/4H Auto To 4L Or 4L To 4H Part Time/
4H Auto
With the vehicle rolling at 2 to 3 mph (3 to
5 km/h), shift the transmission into
NEUTRAL (N). While the vehicle is coasting
at 2 to 3 mph (3 to 5 km/h), shift the
transfer case lever firmly to the desired posi -
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