2006 JEEP WRANGLER engine

•When “rocking” a stuck vehicle by shifting between a
forward gear and reverse, do not spin wheels faster
than 15 mph (24 km/h), or drivetrain damage may
result.
Recommended Manual Transmission Shifting
Speeds
Manual Transmission Shift Speeds in MPH (KM/H)
Engine Speeds 1 to 2 2 to 3 3 to 4 4 to 5 5 to 6
2.4L Accel. 14 (23) 24 (39) 34
(55) 46
(74) 57
(92)
Cruise 11 (18) 19 (31) 27
(43) 38
(61) 45
(72)
4.0L Accel. 15 (24) 24 (39) 34
(55) 47
(76) 56
(90)
Cruise 10 (16) 19 (31) 27
(43) 37
(60) 41
(66)
Clutch Interlocking Ignition System (Non —
Rubicon Models Only)
Manual transmission vehicles are equipped with a clutch
interlock safety feature. With this feature engaged, you
must depress the clutch pedal to allow cranking of the
engine. To temporarily bypass this safety feature while
off-road driving (4L range only), which will allow crank-
ing the engine without depressing the clutch, follow
these steps:
1. Locate the Power Distribution Center (PDC) in the
engine compartment. Refer to “Fuse Panel” in Section 7
of this manual. (See page 305 for more information.)
2. Put a 10 Amp fuse in the PDC cavity (#28) marked as
Clutch Override.
NOTE: A fuse is provided in fuseblock cavity (f19 or
f20) marked as Spare.
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WARNING!
It is dangerous to shift the selector lever out of “P” or
“N” if the engine speed is higher than idle speed. If
your foot is not firmly on the brake pedal, the
vehicle could accelerate quickly forward or in re-
verse. You could lose control of the vehicle and hit
someone or something. Only shift into gear when
the engine is idling normally and when your right
foot is firmly on the brake pedal.
Brake Transmission Shift Interlock System
This vehicle is equipped with a brake transmission shift
interlock system (BTSI) that holds the gearshift lever in
the P (Park) position when the ignition switch is in the
OFF position. To move the gear selector lever out of the
P (Park) position, the ignition switch must be turned to
the ON position, the brake pedal and the button on the
front of the shifter handle must be depressed.
Gear Ranges
P (Park)
Supplements the parking brake by locking the transmis-
sion. The engine can be started in this range. Never use P
(Park) while the vehicle is in motion. Apply the parking
brake when leaving the vehicle in this range. Always
apply the parking brake first, and then place the selector
in P (Park) position.
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WARNING!
Unintended movement of a vehicle could injure
those in and near the vehicle. As with all vehicles,
you should never exit a vehicle while the engine is
running. Before exiting a vehicle, you should always
shift the vehicle into P (Park), remove the key from
the ignition, and apply the parking brake. Once the
key is removed from the ignition, the transmission
shift lever is locked in the P (Park) position, securing
the vehicle against unwanted movement. Further-
more, you should never leave children unattended
inside a vehicle.
The following indicators should be used to ensure that
you have engaged the transmission shift lever into the P
(Park) position:
•When shifting into P (Park), depress the button on the
shift lever and firmly move the lever all the way
forward until it stops.
•Look at the shift indicator window on the console to
ensure it is in the P (Park) position.
•When engaged in P (Park), you will not be able to
move the shifter rearward without depressing the shift
lever button.
CAUTION!
Before moving the shift lever out of P (Park), you
must turn the ignition from LOCK to ON so the
steering wheel and shift lever are released. Other-
wise, damage to the steering column or shifter could
result.
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R (Reverse)
For moving the vehicle rearward. Always stop before
moving the lever to R (Reverse), except when rocking the
vehicle.
N (Neutral)
Engine may be started in this position.
NOTE: Towing the vehicle, coasting, or otherwise driv-
ing with the transmission in N (Neutral) can cause severe
damage to the transmission.
WARNING!
Do not coast in N (Neutral) and never turn off the
ignition to coast down a hill. These are unsafe
practices that limit your response to changing traffic
or road conditions. You might lose control of the
vehicle.
Overdrive (O/D)
For most city and highway driving. The transmission
contains an electronically controlled Overdrive, and will
automatically shift from D (Drive) to O/D (Overdrive) if
the following conditions are present:
•The transmission selector is in D (Drive).
•The O/D OFF switch has not been activated.
•Vehicle speed is above approximately 30 mph (48
km/h).
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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. Overdrive can be locked out by pressing the O/D OFF
switch located on the instrument panel. The O/D OFF
indicator light (on the switch) will illuminate to show
that the switch has been activated. When the indicator
light 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)
For moderate grades and to assist braking on dry pave-
ment or in mud and snow. Begins at a stop in low gear
with automatic upshift to 2nd gear. Will not shift to 3rd.
1 (First)
For hard pulling at low speeds in mud, sand, snow, or on
steep grades. Begins and stays in low gear with no
upshift. Provides engine compression braking at low
speeds.
Overdrive Off Switch
192 STARTING AND OPERATING

WARNING!
Never use P (Park) position with an automatic trans-
mission as a substitute for the parking brake. Al-
ways apply parking brake fully when parked to
guard against vehicle movement and possible injury
or damage.
CAUTION!
•Before moving the shift lever out of P (Park), you
must turn the ignition from LOCK so the steering
wheel and shift lever are released. Otherwise,
damage to steering column or shifter 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 D (Drive) and R (Reverse), do not spin the
wheels faster than 15 mph (24 km/h), or drivetrain
damage may result.
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Operating Instructions/Precautions
The transfer case provides four mode positions — two
(rear) wheel drive high range, four wheel drive high
range, neutral, and four wheel drive low range.
This transfer case is intended to be driven in the two
wheel drive (2H) position for normal street and highway
conditions such as dry hard surfaced roads.
In the events when additional traction is required, the
transfer case 4H and 4L positions can be used to lock the
front and rear driveshafts together and force the front
and rear wheels to rotate at the same speed. This is
accomplished by simply moving the shift lever to these
positions. The 4H and 4L positions are intended for loose,
slippery road surfaces only. Driving in the 4H and 4L
positions on dry hard surfaced roads may cause in-
creased tire wear and damage to the driveline compo-
nents. The 4WD indicator light, located in the instrument panel,
alerts the driver that the vehicle is in four wheel drive
and that the front and rear driveshafts are locked to-
gether. This light illuminates when the transfer case is
shifted to either the 4H or 4L positions.
NOTE:
Do not attempt to make a shift while only the
front or rear wheels are spinning. The transfer case is not
equipped with a synchronizer and therefore the front and
rear driveshafts 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.
When operating your vehicle in 4L, the engine speed is
approximately three times that of the 2H or 4H positions
at a given road speed. Take care not to overspeed the
engine and do not exceed 25 mph (40 km/h).
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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 in
transfer case N (Neutral).
NOTE: Pausing in transfer case N (Neutral) in vehicles
equipped with an automatic transmission may require
shutting the engine OFF to avoid gear clash while
completing the shift. If difficulty occurs, shift the auto-
matic transmission to N (Neutral), hold foot on brake,
and turn the engine OFF. Make shift to desired mode.
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
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
automatically 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
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