light JEEP WRANGLER 2008 Owner's Guide

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.

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!
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!
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.

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

WARNING!
Significant over or under-inflation of tires, or mixing
sizes of tires or wheels on the vehicle can lead to loss
of braking effectiveness.
The Anti-Lock Brake System conducts a low speed self-
test at about 12 mph (20 km/h). If for any reason, your
foot is on the brake when the vehicle reaches 12 mph (20
km/h), this check will be delayed until 25 mph (40
km/h).
The Anti-Lock Brake System pump motor runs during
the self-test, and during an ABS stop, to provide the
regulated hydraulic pressure. The motor pump makes a
low humming noise during operation, this is normal. During off-road use, loss of traction can temporarily
defeat the system and cause the warning light to illumi-
nate. Turn the ignition OFF and ON again to restore
Anti-Lock Brake System function.

inflation pressure of each tire on your vehicle, and inflate
each tire to the vehicle’s recommended cold placard
pressure value. The system will automatically update
and the Tire Pressure Monitoring Telltale Light will
extinguish once the updated tire pressures have been
received. The vehicle may need to be driven for up to 10
minutes above 15 mph (25 km/h) to receive this infor-
mation.
The Tire Pressure Monitoring Telltale Light will flash on
and off for 75 seconds, and will remain on solid when a
system fault is detected. The system fault will also sound
a chime. If the ignition key is cycled, this sequence will
repeat, providing the system fault still exists. A system
fault can occur by any of the following scenarios:
1. Jamming due to electronic devices or driving next to
facilities emitting the same Radio Frequencies as the TPM
sensors.
2. Installing some form of aftermarket window tinting
that affects radio wave signals.3. Lots of snow or ice around the wheels or wheel
housings.
4. Using tire chains on the vehicle.
5. Using wheels/tires not equipped with TPM sensors.
NOTE:
If your vehicle is equipped with a matching
full-size spare wheel and tire assembly, it has a tire
pressure monitoring sensor, and can be monitored by the
Tire Pressure Monitoring System (TPMS). In the event
that the matching full-size spare tire is swapped with a
low pressure road tire, the next ignition key cycle will
still show the Tire Pressure Monitoring Telltale Light to
be ON, and a chime to sound. Driving the vehicle for up
to 10 minutes above 15 mph (25 km/h) will turn OFF the
Tire Pressure Monitoring Telltale Light as long as none of
the road tires are below the low pressure warning thresh-
old.
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FUEL REQUIREMENTS
All engines (except 5.7L engines) are de-
signed to meet all emissions regulations
and provide excellent fuel economy and
performance when using high quality un-
leaded “regular” gasoline having an oc-
tane rating of 87. The use of premium
gasoline is not recommended. Under normal conditions,
the use of premium gasoline will not provide a benefit
over high quality regular gasoline, and in some circum-
stances may result in poorer performance.
Light spark knock at low engine speeds is not harmful to
your engine. However, continued heavy spark knock at
high speeds can cause damage and immediate service is
required. Poor quality gasoline can cause problems such as hard
starting, stalling and hesitations. If you experience these
symptoms, try another brand of gasoline before consid-
ering service for the vehicle.
Over 40 auto manufacturer’s worldwide have issued and
endorsed consistent gasoline specifications (the World-
wide Fuel Charter, WWFC) to define fuel properties
necessary to deliver enhanced emissions, performance,
and durability for your vehicle. The manufacturer recom-
mends the use of gasoline that meets the WWFC speci-
fications if they are available.
Reformulated Gasoline
Many areas of the country require the use of cleaner
burning gasoline referred to as “Reformulated Gasoline.”
Reformulated gasoline contains oxygenates, and are spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.

ADDING FUEL
Fuel Filler Cap (Gas Cap)
The gas cap is located on the driver’s side of the vehicle.
If the gas cap is lost or damaged, be sure the replacement
cap is the correct one for this vehicle.
Loose Fuel Filler Cap Message (gASCAP)
After fuel has been added, the vehicle diagnostic system
can determine if the fuel filler cap is possibly loose,
improperly installed, or damaged. If the system detects a
malfunction, the “gASCAP” message will display in the
odometer display. Tighten the gas cap until aclicking
sound is heard. This is an indication that the gas cap is
properly tightened. Press the odometer reset button to
turn the message off. If the problem persists, the message
will appear the next time the vehicle is started. This
might indicate a damaged cap. If the problem is detected
twice in a row, the system will turn on the Malfunction
Indicator Light. Resolving the problem will turn the MIL
light off.

If using a manual transmission vehicle for trailer towing,
all starts must be in 1st gear to avoid excessive clutch
slippage.
Towing Tips — Automatic Transmission
The DRIVE range can be selected when towing. How-
ever, if frequent shifting occurs while in this range, the
OVERDRIVE range should be selected.
NOTE:Using “O/D OFF” while operating the vehicle
under heavy operating conditions will improve perfor-
mance and extend transmission life by reducing exces-
sive shifting and heat build up. This action will also
provide better engine braking.
The automatic transmission fluid and filter should be
changed if you REGULARLY tow a trailer for more than
45 minutes of continuous operation. Refer to the “Main-
tenance Schedule” in Section 8 of this manual for trans-
mission fluid change intervals. NOTE:
Check the automatic transmission fluid level
before towing.
Towing Tips — O/D Off
To reduce potential for automatic transmission overheat-
ing, select the “O/D OFF” feature when driving in hilly
areas or shift the transmission to DRIVE position 2 on
more severe grades. Refer to “Transmission Shifting” in
this section.
Towing Tips — Electronic Speed Control (If
Equipped)

Don’t use in hilly terrain or with heavy loads.
When using the speed control, if you experience speed
drops greater than 10 mph (16 km/h), disengage until
you can get back to cruising speed.
Use speed control in flat terrain and with light loads to
maximize fuel efficiency.
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