2008 JEEP WRANGLER engine

Trac-Lok™ is especially helpful during slippery driving
conditions. With both rear wheels on a slippery surface, a
slight application of the accelerator will supply maxi-
mum traction.
WARNING!
On vehicles equipped with a limited-slip differen-
tial, never run the engine with one rear wheel off the
ground. The vehicle may drive through the rear
wheel remaining on the ground and cause you to lose
control of your vehicle.
AXLE LOCK (TRU–LOK™) — RUBICON MODELS
The AXLE LOCK switch is located on the lower switch
bank (below the climate controls).
This feature will only activate when the following con-
ditions are met:
•Key in ignition, vehicle in 4L (Low) range.
Axle Lock Switch
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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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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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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.
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The manufacturer supports the use of reformulated gaso-
line. Properly blended reformulated gasoline will pro-
vide excellent performance and durability for the engine
and fuel system components.
Gasoline/Oxygenate Blends
Some fuel suppliers blend unleaded gasoline with oxy-
genates such as 10% ethanol, MTBE, and ETBE. Oxygen-
ates are required in some areas of the country during the
winter months to reduce carbon monoxide emissions.
Fuels blended with these oxygenates may be used in
your vehicle.
CAUTION!
DO NOT use gasolines containing Methanol. Use of
these blends may result in starting and drivability
problems and may damage critical fuel system
components.Problems that result from using methanol/gasoline
blends are not the responsibility of the manufacturer.
While MTBE is an oxygenate made from Methanol, it
does not have the negative effects of Methanol.
MMT In Gasoline
MMT is a manganese containing metallic additive that is
blended into some gasoline to increase the octane num-
ber. Gasoline blended with MMT offers no performance
advantage beyond gasoline of the same octane number
without MMT. Gasoline blended with MMT has shown
to reduce sparkplug life and reduce emission system
performance in some vehicles. The manufacturer recom-
mends that gasoline without MMT be used in your
vehicle. The MMT content of gasoline may not be indi-
cated on the gasoline pump, therefore, you should ask
your gasoline retailer if the gasoline contains MMT.
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