engine JEEP WRANGLER 2009 JK / 3.G Service Manual

REVERSE
This range is for moving the vehicle backward. Use only
after the vehicle has come to a complete stop.
NEUTRAL
This range is used when vehicle is standing for pro-
longed periods with engine running. Engine may be
started in this range. Set the parking brake if you must
leave the vehicle.
NOTE:Towing, coasting, or driving the vehicle for any
other reason with the shift lever in NEUTRAL can result
in severe transmission damage. Refer to “Recreational
Towing” in Section 5 and “Towing a Disabled Vehicle” in
Section 6 of this manual. OVERDRIVE
This range is used for most city and highway driving.
The transmission contains an electronically-controlled
fourth gear Overdrive, and will automatically shift from
DRIVE to OVERDRIVE if the following conditions are
present:
•The shift lever is in DRIVE.
•The O/D OFF switch has not been activated.
•Vehicle speed is above approximately 30 mph
(48 km/h).
When frequent transmission shifting occurs while using
Overdrive, such as when operating the vehicle under
heavy load conditions (for example, in hilly terrain,
strong head winds, or trailer towing), turning off over-
drive will improve performance and extend transmission
life by reducing excessive shifting and heat buildup.5
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If the transmission overheats, a “HOTOIL” message will
be displayed in the odometer and a chime will sound.
Overdrive can be locked out by pressing the O/D OFF
switch located on the center console. The “O/D OFF
Indicator Light” (on the switch) will illuminate to show
that the switch has been activated. When the indicatorlight is on, Overdrive is locked out. Pressing the switch a
second time restores the Overdrive function. The lockout
feature is useful when towing a trailer or carrying a
heavy load.
2 (Second)
This range is used for moderate grades and to assist
braking on dry pavement or in mud and snow. The
vehicle begins from a stop in low gear with automatic
upshift to second gear. The vehicle will not shift into
third gear.
1 (First)
This range is used for hard pulling at low speeds in mud,
sand, snow, or on steep grades. The vehicle begins and
stays in low gear with no upshift. This gear provides
engine compression braking at low speeds.
Overdrive Off Switch
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CAUTION!
•Before moving the shift lever out of PARK, you
must turn the ignition from LOCK so the steering
wheel and shift lever are released. Otherwise,
damage to the steering column or shift lever could
result.
•Never race the engine with the brakes on and the
vehicle in gear, and never hold the vehicle on an
incline without applying the brakes. These prac-
tices can overheat and damage the transmission.
•When “rocking” a stuck vehicle by moving be-
tween DRIVE and REVERSE, do not spin the
wheels faster than 15 mph (24 km/h), or drivetrain
damage may result.
Torque Converter Clutch
A feature designed to improve fuel economy has been
added to the automatic transmission of this vehicle. A
clutch within the torque converter engages automatically
at calibrated speeds. This may result in a slightly differ-
ent feeling or response during normal operation in high
gear. When the vehicle speed drops or during accelera-
tion, the clutch automatically and smoothly disengages.
FOUR–WHEEL DRIVE OPERATION (COMMAND-
TRAC IOR ROCK-TRAC) — IF EQUIPPED
Operating Instructions/Precautions
The transfer case provides four mode positions:
•2H (Two-wheel drive high range)
•4H (Four-wheel drive high range)
•N (Neutral)
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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 only the front or rear wheels are spinning
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!
You or others could be injured if you leave the
vehicle unattended with the transfer case in the N
(Neutral) position without first fully engaging the
parking brake. The transfer case N (Neutral) position
disengages both the front and rear driveshaft from
the powertrain, and will allow the vehicle to move
regardless of the transmission position. 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
transfer case 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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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 lower switch
bank (below the climate controls).This feature will only activate when the following con-
ditions are met:
•Key in ignition, vehicle in 4L (Low) range.
•Vehicle speed should be 10 mph (16 km/h) or less.
Axle Lock Switch
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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 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 freshbiteand 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
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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
and maintain headway by turning the steering wheel no
more than a 1/4 turn quickly back and forth. This will
provide a freshbiteinto 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.
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Driving Across an Incline
If at all possible, avoid driving across an incline. If it is
necessary, know your vehicle’s abilities. Driving across
an incline places more weight on the downhill wheels,
which increases the possibilities of a downhill slide or
rollover. Make sure the surface has good traction with
firm and stable soils. If possible, transverse the incline at
an angle heading slightly up or down.
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 allowingengine 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
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designated and approved. You should tread lightly and
avoid damage to the environment. You should know
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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system. This noise should be considered normal, and it
does not in any way damage the steering system.
WARNING!
Continued operation with reduced power steering
assist could pose a safety risk to yourself and others.
Service should be obtained as soon as possible.
CAUTION!
Prolonged operation of the steering system at the end
of the steering wheel travel will increase the steering
fluid temperature and it should be avoided when
possible. Damage to the power steering pump may
occur.
Power Steering Fluid Check
Checking the power steering fluid level at a defined
service interval is not required. The fluid should only bechecked if a leak is suspected, abnormal noises are
apparent, and/or the system is not functioning as antici-
pated. Coordinate inspection efforts through an autho-
rized dealer.
CAUTION!
Do not use chemical flushes in your power steering
system as the chemicals can damage your power
steering components. Such damage is not covered by
the New Vehicle Limited Warranty.
WARNING!
Fluid level should be checked on a level surface and
with the engine off to prevent injury from moving
parts and to ensure accurate fluid level reading. Do
not overfill. Use only manufacturer’s recommended
power steering fluid.
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