JEEP WRANGLER 2008 JK / 3.G Owners Manual
Manufacturer: JEEP, Model Year: 2008, Model line: WRANGLER, Model: JEEP WRANGLER 2008 JK / 3.GPages: 466, PDF Size: 8.97 MB
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CAUTION!
Never attempt to straddle a rock that is large enough
to strike your axles or undercarriage.
CAUTION!
Never attempt to drive over a rock which is large
enough to contact the door sills.
Crossing A Ravine, Gully, Ditch, Washout Or Rut
When crossing a ravine, gully, ditch, washout or a large
rut, the angled approach is the key to maintaining your
vehicle’s mobility. Approach these obstacles at a 45-
degree angle and let each tire go through the obstacle
independently. You need to use caution when crossing
large obstacles with steep sides. Do not attempt to crossany large obstacle with steep sides at an angle great
enough to put the vehicle at risk of a rollover. If you get
caught in a rut, dig a small trench to the right or left at a
45-degree angle ahead of the front tires. Use the removed
dirt to fill the rut ahead of the turnout you just created.
You should now be able to drive out following the trench
you just created at a 45-degree angle.
WARNING!
There is an increased risk of rollover when crossing
an obstacle, at any angle, with steep sides.
Crossing Logs
To cross a log, approach it at a slight angle (approxi-
mately 10 to 15 degrees). This allows one front tire to be
on top of the log while the other just starts to climb the
log. While climbing the log, modulate your brake and
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accelerator to avoid spinning the log out from under your
tires. Then ease the vehicle off the log using your brakes.
CAUTION!
Do not attempted to cross a log with a greater
diameter than the running ground clearance or the
vehicle will become high centered.
Getting High-Centered
If you get hung up or high-centered on an object, get out
of the vehicle and try to determine what the vehicle is
hung up on, where it is contacting the underbody and
what is the best direction to recover the vehicle. Depend-
ing on what you are in contact with, jack the vehicle up
and place a few rocks under the tires so the weight is off
of the high point when you let the vehicle down. You can
also try rocking the vehicle or winching the vehicle off
the object.
CAUTION!
Winching or rocking the vehicle off hard objects
increases the risk of underbody damage.
Hill Climbing
Hill climbing requires good judgment and a good under-
standing of your abilities and your vehicle’s limitations.
Hills can cause serious problems. Some are just too steep
to climb and should not be attempted. You should always
feel confident with the vehicle and your abilities. You
should always climb hills straight up and down. Never
attempt to climb a hill on an angle.
Before Climbing A Steep Hill
As you approach a hill consider its grade or steepness.
Determine if it is too steep. Look to see what the traction
is on the hill side trail. Is the trail straight up and down?
What is on top and the other side? Are there ruts, rocks,
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branches or other obstacles on the path? Can you safely
recover the vehicle if something goes wrong? If every-
thing looks good and you feel confident, shift the trans-
mission into a lower gear with 4L (Low) engaged, and
proceed with caution maintaining your momentum as
you climb the hill.
Driving Up Hill
Once you have determined your ability to proceed and
have shifted into the appropriate gear, line your vehicle
up for the straightest possible run. Accelerate with an
easy constant throttle and apply more power as you start
up the hill. Do not race forward into a steep grade, the
abrupt change of grade could cause you to lose control. If
the front end begins to bounce, ease off the throttle
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 nomore than a 1/4 turn quickly back and forth. This will
provide a fresh
biteinto 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 Down Hill
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
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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.
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 orrollover. 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 allowing
engine braking to control the descent and apply your
brakes if necessary, but do not allow the tires to lock.
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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 man-
ner. You should only drive through areas which are
designated and approved. You should tread lightly andavoid damage to the environment. You should know
your vehicles abilities and be able to recover it if some-
thing 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 1st gear (manual transmission), or DRIVE (automatic
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 inges-
tion.
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CAUTION!
Water ingestion into the axles, transmission, transfer
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.
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
muddy waters, check for hidden obstacles. Make sure
you will not be intruding on any wildlife and you can
recover the vehicle if necessary. The key to a safe crossingis the water depth, current and bottom conditions. On
soft bottoms the vehicle will sink in, effectively increas-
ing the water level on the vehicle. Be sure to consider this
when determining the depth and the ability to safely
cross
Crossing Puddles, Pools, Flooded Areas Or Other
Standing Water
Puddles, pools, flooded or other standing water areas
normally contain murky or muddy waters. These water
types normally contain hidden obstacles and make it
difficult to determine an accurate water depth, approach
angle, and bottom condition. Murky or muddy water
holes are where you want to hook up tow straps prior to
entering. This makes for a faster, cleaner and easier
vehicle recovery. If you are able to determine you can
safely cross, than proceed using the low and slow
method.
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CAUTION!
Muddy waters can reduce the cooling system effec-
tiveness by depositing debris onto the radiator.
Crossing Ditches, Streams, Shallow Rivers Or
Other Flowing Water
Flowing water can be extremely dangerous. Never at-
tempt to cross a fast running stream or river even in
shallow water. Fast moving water can easily push your
vehicle downstream sweeping it out of control. Even in
very shallow water, a high current can still wash the dirt
out from around your tires putting you and your vehicle
in jeopardy. There is still a high risk of personal injury
and vehicle damage with slower water currents in depths
greater than the vehicle’s running ground clearance. You
should never attempt to cross flowing water which is
deeper than the vehicle’s running ground clearance. Eventhe slowest current can push the heaviest vehicle down-
stream out of control if the water is deep enough to push
on the large surface area of the vehicle’s body. Before you
proceed determine the speed of the current, the water’s
depth, approach angle, bottom condition and if there are
any obstacles, then cross at an angle heading slightly
upstream using the low and slow technique.WARNING!
Never drive through fast moving deep water. It can
push your vehicle downstream, sweeping it out of
control. This could put you and your passengers at
risk of injury or drowning.
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After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road it is
always a good idea to check for damage. That way you
can get any problems taken care of right away and have
your vehicle ready when you need it.
•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
•Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
•Check for accumulations of plants or brush. These
things could be a fire hazard. They might hide damage
to fuel lines, brake hoses, axle pinion seals, and
propeller shafts.
•After extended operation in mud, sand, water, or
similar dirty conditions, have the radiator, brake ro-
tors, wheels, brake linings, and axle yokes inspected
and cleaned as soon as possible.
WARNING!
Abrasive material in any part of the brakes may cause
excessive wear or unpredictable braking. You might
not have full braking power when you need it to
prevent an accident. If you have been operating your
vehicle in dirty conditions, get your brakes checked
and cleaned as necessary.
•If you experience unusual vibration after driving in
mud, slush or similar conditions, check the wheels for
impacted material. Impacted material can cause a
wheel imbalance and freeing the wheels of it will
correct the situation.
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PARKING BRAKE
To set the parking brake, pull the lever up as firmly as
possible. When the parking brake is applied with the
ignition ON, the Brake Warning Light in the instrument
cluster will light. To release the parking brake, pull up
slightly, press the center button, then lower the lever
completely.
NOTE:The instrument cluster Brake Warning Light
indicates only that the parking brake is applied. You must
be sure the parking brake is fully applied before leaving
the vehicle.
Be sure the parking brake is firmly set when parked, and
the shift lever is in the PARK position (automatic trans-
mission), or REVERSE, or 1st gear (manual transmission).
When parking on a hill, you should apply the parking
brake before placing the shift lever in PARK, otherwise
Parking Brake
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the load on the transmission locking mechanism may
make it difficult to move the shifter out of PARK.
WARNING!
•Always fully apply the parking brake when leav-
ing your vehicle, or it may roll and cause damage
or injury. Also, be certain to leave an automatic
transmission in PARK, a manual transmission in
REVERSE or 1st gear. Failure to do so may allow
the vehicle to roll and cause damage or injury.
•Never leave children alone in a vehicle. Leaving
unattended children in a vehicle is dangerous for a
number of reasons. A child or others could be
seriously or fatally injured. Do not leave the key in
the ignition. A child could operate power win-
dows, other controls, or move the vehicle.When parking on a hill, turn the front wheels toward the
curb on a downhill grade and away from the curb on an
uphill grade.
The parking brake should always be applied whenever
the driver is not in the vehicle.
ANTI-LOCK BRAKE SYSTEM
The Anti-Lock Brake System (ABS) is designed to aid the
driver in maintaining vehicle control under adverse
braking conditions. The system operates with a separate
computer to modulate hydraulic pressure to prevent
wheel lock-up and help avoid skidding on slippery
surfaces.
All vehicle wheels and tires must be the same size and
type and tires must be properly inflated to produce
accurate signals for the computer.
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