2008 JEEP WRANGLER Owners Manual

The Basics of Off-Road Driving
You will encounter many types of terrain driving off-
road. You should be familiar with the terrain and area
before proceeding. There are many types of surface
conditions: hard packed dirt, gravel, rocks, grass, sand,
mud, snow and ice. Every surface has a different effect on
your vehicle’s steering, handling and traction. Control-
ling your vehicle is one of the keys to successful off-road
driving, so always keep a firm grip on the steering wheel
and maintain a good driving posture. Avoid sudden
accelerations, turns or braking. In most cases there are no
road signs, posted speed limits or signal lights. Therefore
you will need to use your own good judgment on what is
safe and what isn’t. When on a trail you should always be
looking ahead for surface obstacles and changes in
terrain. The key is to plan your future driving route while
remembering what you are currently driving over.CAUTION!
Never park your vehicle over dry grass or other
combustible materials. The heat from your vehicle
exhaust system could cause a fire.
WARNING!
Always wear your seat belt and firmly tie down
cargo. Unsecured cargo can become projectiles in an
off-road situation.
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When To Use 4L (Low) Range
When off-road driving, shift into 4L (Low) for additional
traction and control on slippery or difficult terrain,
ascending or descending steep hills, and to increase low
speed pulling power. This range should be limited to
extreme situations such as deep snow, mud, steep in-
clines, or sand where additional low speed pulling power
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. Don’t 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.
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Mud
Deep mud creates a great deal of suction around the tires
and is very difficult to get through. You should use 2nd
gear (manual transmission), or DRIVE (automatic trans-
mission), 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
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 tirepressure, 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 han-
dling, while driving on the soft sand, but you must return
the tires to normal air pressure before driving on pave-
ment 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.
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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.
WARNING!
Crossing obstacles can cause abrupt steering system
loading which could cause you to loose control of
your vehicle.
Using A Spotter
There are many times where it is hard to see the obstacle
or determine the correct path. Determining the correct
path can be extremely difficult when you are confronting
many obstacles. In these cases have someone guide you
over, through, or around the obstacle. Have the person
stand a safe distance in front of you where they can see
the obstacle, watch your tires and undercarriage, and
guide you through.
Crossing Large Rocks
When approaching large rocks, choose a path which
ensures you drive over the largest of them with your
tires. This will lift your undercarriage over the obstacle.
The tread of the tire is tougher and thicker than the side
wall and is designed to take the abuse. Always look
ahead and make every effort to cross the large rocks with
your tires.
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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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