2010 JEEP WRANGLER stop start

4H to 4L or 4L to 4H
With the vehicle rolling at 2 to 3 mph (3 to 5 km/h), shift
an automatic transmission into NEUTRAL (N), or press
the clutch pedal on a manual transmission. While the
vehicle is coasting at 2 to 3 mph (3 to 5 km/h), shift the
transfer case lever firmly to the desired position. Do not
pause with the transfer case in N (Neutral).
NOTE:Shifting into or out of 4L is possible with the
vehicle completely stopped; however, difficulty may oc-
cur due to the mating teeth not being properly aligned.
Several attempts may be required for clutch teeth align-
ment 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).WARNING!
Failure to engage a position completely can cause
transfer case damage or loss of power and vehicle
control. You could have an injury accident. Do not
drive the vehicle unless the transfer case is fully
engaged.
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.5
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is needed. Vehicle speeds in excess of 25 mph (40 km/h)
should be avoided when in 4L (Low) range.
Simultaneous Brake and Throttle Operation
Many off-road driving conditions require the simulta-
neous 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 yoursteering 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
biteand 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.
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
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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
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
handling while driving on the soft sand, but you must
return the tires to normal air pressure before driving on
pavement 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 maneuvers.
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.
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WARNING!
Driving across an incline increases the risk of a
rollover, which may result in severe injury.
If You Stall or Begin to Lose Headway
If you stall or begin to lose headway while climbing a
steep hill, allow your vehicle to come to a stop and
immediately apply the brake. Restart the engine and shift
into REVERSE. Back slowly down the hill allowing
engine braking to control the descent and apply your
brakes, if necessary, but do not allow the tires to lock.
WARNING!
If the engine stalls or you lose headway or cannot
make it to the top of a steep hill or grade, never
attempt to turn around. To do so may result in
tipping and rolling the vehicle, which may result in
severe injury. Always back carefully straight down a
hill in REVERSE gear. Never back down a hill in
NEUTRAL using only the vehicle brakes. Never
drive diagonally across a hill; always drive straight
up or down.
Driving Through Water
Extreme care should be taken crossing any type of water.
Water crossings should be avoided, if possible, and only
be attempted when necessary in a safe, responsible
manner. You should only drive through areas which are
designated and approved. You should tread lightly and
avoid damage to the environment. You should know
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your vehicle’s abilities and be able to recover it if
something goes wrong. You should never stop or shut a
vehicle off when crossing deep water unless you ingested
water into the engine air intake. If the engine stalls, do
not attempt to restart it. Determine if it has ingested
water first. The key to any crossing is low and slow. Shift
into first gear (manual transmission), or DRIVE (auto-
matic transmission), with the transfer case in the 4L
(Low) position and proceed very slowly with a constant
slow speed {3 to 5 mph (5 to 8 km/h) maximum} and
light throttle. Keep the vehicle moving; do not try to
accelerate through the crossing. After crossing any water
higher than the bottom of the axle differentials, you
should inspect all of the vehicle fluids for signs of water
ingestion.CAUTION!
•Water ingestion into the axles, transmission, trans-
fer case, engine or vehicle interior can occur if you
drive too fast or through too deep of water. Water
can cause permanent damage to engine, driveline
or other vehicle components, and your brakes will
be less effective once wet and/or muddy.
•This vehicle is capable of crossing through water
at a depth of 30 inches (76 cm) at speeds no greater
than 5 mph (8 km/h). Water ingestion can occur
causing damage to your vehicle.
Before You Cross Any Type of Water
As you approach any type of water, you need to deter-
mine if you can cross it safely and responsibly. If neces-
sary, get out and walk through the water or probe it with
a stick. You need to be sure of its depth, approach angle,
current and bottom condition. Be careful of murky or
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The Anti-Lock Brake System pump motor runs during
the self-test, and during an ABS stop, to provide the
regulated hydraulic pressure. The motor pump makes a
low humming noise during operation; this is normal.
WARNING!
•Pumping of the Anti-Lock Brakes will diminish
their effectiveness and may lead to an accident.
Pumping makes the stopping distance longer. Just
press firmly on your brake pedal when you need
to slow down or stop.
•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.(Continued)
WARNING! (Continued)
•The ABS cannot prevent accidents, including
those resulting from excessive speed in turns,
following another vehicle too closely, or hydro-
planing.
•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.
CAUTION!
The Anti-Lock Brake System is subject to possible
detrimental effects of electronic interference caused
by improperly installed aftermarket radios or tele-
phones.
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Traction Control System (TCS)
This system monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, brake
pressure is applied to the slipping wheel(s) to provide
enhanced acceleration and stability. A feature of the TCS
system 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 ESP are in either the “Partial Off” or “Full Off”
modes. Refer to “ESP (Electronic Stability Program)” in
this section.
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 very
quickly 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.
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WARNING!
The Brake Assist System (BAS) cannot prevent the
natural laws of physics from acting on the vehicle,
nor can it increase the traction afforded by prevailing
road conditions. The BAS cannot prevent accidents,
including those resulting from excessive speed in
turns, driving on very slippery surfaces, or hydro-
planing. The capabilities of a BAS-equipped vehicle
must never be exploited in a reckless or dangerous
manner which could jeopardize the user’s safety or
the safety of others.
Hill Start Assist (HSA)
The HSA system is designed to assist the driver when
starting a vehicle from a stop on a hill. HSA will maintain
the level of brake pressure the driver applied for a short
period of time after the driver takes their foot off of the
brake pedal. If the driver does not apply the throttleduring this short period of time, the system will release
brake pressure and the vehicle will roll down the hill. The
system will release brake pressure in proportion to
amount of throttle applied as the vehicle starts to move in
the intended direction of travel.
WARNING!
If the clutch pedal (manual transmission only) re-
mains pressed during the application of the throttle,
the HSA will disengage allowing the vehicle to roll
down the incline. This could cause a collision with
another vehicle or object. To avoid this, do not apply
throttle while pressing the clutch pedal until you are
ready to release the clutch. Always remember the
driver is responsible for braking the vehicle.
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