JEEP WRANGLER 2008 JK / 3.G Owners Manual

Vehicle Loading ........................342
▫ Certification Label .....................342
 Trailer Towing .........................344
▫ Common Towing Definitions .............345
▫ Trailer Hitch Classification ...............348
▫ Trailer Towing Weights (Maximum Trailer
Weight Ratings) ......................348 ▫
Trailer And Trailer Tongue Weight .........352
▫ Towing Requirements ..................353
▫ Towing Tips .........................357
 Recreational Towing (Behind Motorhome, Etc.) . . 359
▫ Towing – 2WD Models .................359
▫ Towing – 4WD Models .................360
270 STARTING AND OPERATING

STARTING PROCEDURES
Before starting your vehicle, adjust your seat, adjust both
inside and outside mirrors, and fasten your seat belts.
WARNING!
Do not leave children or animals inside parked
vehicles in hot weather. Interior heat buildup may
cause serious injury or death.
Manual Transmission
Apply the parking brake, place the shift lever in NEU-
TRAL and depress the clutch pedal before starting ve-
hicle. This vehicle is equipped with a clutch interlocking
ignition system. It will not start unless the clutch pedal is
pressed to the floor.4WD Models Only
In 4L mode, this vehicle will start regardless of whether
or not the clutch pedal is pressed to the floor. This feature
enhances off-road performance by allowing the vehicle to
start when in 4L without having to depress the clutch
pedal. The 4WD Indicator Light will illuminate when the
transfer case has been shifted into this mode.
Automatic Transmission
Start the engine with the shift lever in the NEUTRAL or
PARK position. Apply the brake before shifting to any
driving range.
Normal Starting
NOTE:
Normal starting of either a cold or a warm
engine is obtained without pumping or depressing the
accelerator pedal.
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Turn the ignition switch to the START position and
release when the engine starts. If the engine fails to start
within 10 seconds, turn the ignition switch to the LOCK
position, wait 10 to 15 seconds, then repeat the normal
starting procedure.
Tip Start Feature — Automatic Transmission Only
Turn the ignition switch to START position and release it
as soon as the starter engages. The starter motor will
continue to run, but will automatically disengage itself
when the engine is running. If the engine fails to start, the
starter will disengage automatically in 10 seconds. If this
occurs, turn the ignition switch to the LOCK position,
wait 10 to 15 seconds, then repeat the normal starting
procedure.
Extreme Cold Weather (below –20°F or –29°C)
To ensure reliable starting at these temperatures, use of
an externally-powered electric engine block heater (avail-
able from your authorized dealer) is recommended.
Ignition Key Positions
272 STARTING AND OPERATING

If Engine Fails to Start
WARNING!
•Never pour fuel or other flammable liquids into
the throttle body air inlet opening in an attempt to
start the vehicle. This could result in a flash fire
causing serious personal injury.
• Do not attempt to push or tow your vehicle to get
it started. Vehicles equipped with an automatic
transmission cannot be started this way. Unburned
fuel could enter the catalytic converter and once
the engine has started, ignite and damage the
converter and vehicle. If the vehicle has a dis-
charged battery, booster cables may be used to
obtain a start from a booster battery or the battery
in another vehicle. This type of start can be dan-
gerous if done improperly. Refer to Section 6 of
this manual for proper jump starting procedures
and follow them carefully.
Without Tip Start (Manual Transmission Only)
If the engine fails to start after you have followed the
“Normal Starting” or “Extreme Cold Weather” proce-
dures, it may be flooded. Push the accelerator pedal all
the way to the floor and hold it there while cranking the
engine. This should clear any excess fuel in case the
engine is flooded.
CAUTION!
To prevent damage to the starter, do not crank the
engine for more than 15 seconds at a time. Wait 10 to
15 seconds before trying again.
If the engine has been flooded, it may start to run, but not
have enough power to continue running when the key is
released. If this occurs, continue cranking with the accel-
erator pedal pushed all the way to the floor. Release the
accelerator pedal and the key once the engine is running
smoothly.
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If the engine shows no sign of starting after two 15
second periods of cranking with the accelerator pedal
held to the floor, repeat the “Normal Starting” or “Ex-
treme Cold Weather” procedures.
With Tip Start (Automatic Transmission Only)
If the engine fails to start after you have followed the
“Normal Starting” or “Extreme Cold Weather” proce-
dures, it may be flooded. To clear any excess fuel, push
the accelerator pedal all the way to the floor and hold it.
Then, turn the ignition switch to the START position and
release it as soon as the starter engages. The starter motor
will disengage automatically in 10 seconds. Once this
occurs, release the accelerator pedal, turn the ignition
switch to the LOCK position, wait 10 to 15 seconds, then
repeat the normal starting procedure.CAUTION!
To prevent damage to the starter, wait 10 to 15
seconds before trying again.
After Starting
The idle speed will automatically decrease as the engine
warms up.
WARNING!
Do not leave children or animals inside parked
vehicles in hot weather. Interior heat buildup may
cause serious injury or death.
274 STARTING AND OPERATING

ENGINE BLOCK HEATER — IF EQUIPPED
The engine block heater warms engine coolant and
permits quicker starts in cold weather. Connect the cord
to a standard 110-115 Volt AC electrical outlet with a
grounded, three wire extension cord. The engine block
heater cord is found under the hood bundled in front of
the battery tray.
WARNING!
Remember to disconnect the cord before driving.
Damage to the 110-115 Volt AC electrical cord could
cause electrocution.
Use the heater when temperatures below 0°F (-18°C) are
expected to last for several days.
MANUAL TRANSMISSION
WARNING!
You or others could be injured if you leave the
vehicle unattended without having the parking
brake fully applied. The parking brake should al-
ways be applied when the driver is not in the vehicle,
especially on an incline.
CAUTION!
Never drive with your foot resting on the clutch
pedal, or attempt to hold the vehicle on a hill with the
clutch pedal partially engaged, as this will cause
abnormal wear on the clutch.
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NOTE:During cold weather, you may experience in-
creased effort in shifting until the transmission fluid
warms up. This is normal.Shifting
Fully depress the clutch pedal before shifting gears. As
you release the clutch pedal, lightly depress the accelera-
tor pedal.
You should always use 1st gear when starting from a
standing position if under heavy load or when pulling a
trailer.
Recommended Vehicle Shift Speeds
To utilize your manual transmission efficiently for both
fuel economy and performance, it should be upshifted as
listed in recommended shift speed chart. Shift at the
vehicle speeds listed for acceleration. When heavily
loaded or pulling a trailer these recommended up-shift
speeds may not apply.
Shift Pattern
276 STARTING AND OPERATING

Manual Transmission Shift Speeds in MPH (KM/H)
En-
gine Speeds 1 to 2 2 to 3 3 to 4 4 to 5 5 to 6
3.8L Accel. 15 (24) 24 (39)34
(55) 47
(76) 56
(90)
Cruise 10 (16) 19 (31)27
(43) 37
(60) 41
(66)
Downshifting
Moving from a high gear down to a lower gear is
recommended to preserve brakes when driving down
steep hills. In addition, downshifting at the right time
provides better acceleration when you desire to resume
speed. Downshift progressively. Do not skip gears to
avoid overspeeding the engine and clutch.
WARNING!
Do not downshift for additional engine braking on a
slippery surface. The drive wheels could lose their
grip and the vehicle could skid.
CAUTION!
When descending a hill, be very careful to downshift
one gear at a time to prevent overspeeding the engine
which can cause valve damage, and/or clutch disc
damage even if the clutch pedal is depressed.
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Maximum Recommended Downshift Speeds
CAUTION!
Failure to follow the maximum recommended down-
shifting speeds may cause the engine to overspeed
and/or damage the clutch disc even if the clutch pedal
is depressed.
Manual Transmission Downshift Speeds in MPH(KM/H)
Gear
Selec-
tion 6to5 5to4 4to3 3to2 2to1
Maxi-
mum
Speed 80 (129) 70 (113) 50 (81) 30 (48) 15 (24)
Reverse Shifting
To shift into REVERSE, bring the vehicle to a complete
stop. Depress the clutch and pause briefly to allow the
gear train to stop rotating. Beginning from the NEUTRAL
position, move the shift lever in one quick smooth
motion straight across and into the REVERSE area (the
driver will feel a firm “click” as the shifter passes the
“knock-over”). Complete the shift by pulling the shift
lever into REVERSE.
The “knock-over” prevents the driver from accidentally
entering the REVERSE shift area and warns the driver
that they are about to shift the transmission into RE-
VERSE. Due to this feature, a slow shift to REVERSE can
be perceived as a high shift effort.
278 STARTING AND OPERATING

AUTOMATIC TRANSMISSION
CAUTION!
Damage to the transmission may occur if the follow-
ing precautions are not observed:
•Shift into PARK only after the vehicle has come to
a complete stop.
•Shift into or out of REVERSE only after the
vehicle has come to a complete stop and the engine
is at idle speed.
•Do not shift from REVERSE, PARK, or NEUTRAL
into any forward gear when the engine is above
idle speed.
•Before shifting into any gear, make sure your foot
is firmly on the brake pedal.
WARNING!
It is dangerous to move the shift lever out of PARK or
NEUTRAL 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
reverse. 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 foot is
firmly on the brake pedal.
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