engine oil JEEP WRANGLER 2008 JK / 3.G Owners Manual

ENGINE BREAK-IN RECOMMENDATIONS
A long break-in period is not required for the engine in
your vehicle.
Drive moderately during the first 300 mi (500 km). After
the initial 60 mi (100 km), speeds up to 50 or 55 mph (80
or 90 km/h) are desirable.
While cruising, brief full-throttle acceleration, within the
limits of local traffic laws, contributes to a good break-in.
Wide-open throttle acceleration in low gear can be detri-
mental and should be avoided.
The engine oil installed in the engine at the factory is a
high-quality energy-conserving type lubricant. Oil
changes should be consistent with anticipated climate
conditions under which vehicle operations will occur. For
the recommended viscosity and quality grades, refer to
“Maintenance Procedures” in Section 7 of this manual.
NON-DETERGENT OR STRAIGHT MINERAL OILS
MUST NEVER BE USED.A new engine may consume some oil during its first few
thousand miles (kilometers) of operation. This should be
considered as a normal part of the break-in and not
interpreted as an indication of difficulty.
SAFETY TIPS
Exhaust Gas
WARNING!
Exhaust gases can injure or kill. They contain carbon
monoxide (CO) which is colorless and odorless.
Breathing it can make you unconscious and can
eventually poison you. To avoid breathing (CO)
follow the safety tips below.
THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 75
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INSTRUMENT CLUSTER DESCRIPTION
Your vehicle is equipped with the instrument cluster
described on the following pages.
1. Fuel Gauge
The pointer shows the level of fuel in the fuel tank.
NOTE:When the ignition switch is turned to OFF, the
fuel gauge, voltmeter, oil pressure and temperature
gauges may not show accurate readings. When the
engine is not running, turn the ignition switch to ON to
obtain accurate readings.
2. Charging System Warning Light This light shows the status of the electrical charg-
ing system. The light should come on for three
seconds when the ignition is first turned ON. If the light
comes back on immediately or comes on while driving, it
means that there is a problem with the charging system
or the battery is low. Also, a chime will sound if the light
comes back on. See your authorized dealer immediately. 3. Front Fog Light Indicator Light — If Equipped
This light shows when the front fog lights are on.
4. Low Fuel Warning Light When the fuel level reaches approximately 2.8 gal
(10.6L) this light will turn on and a single chime
will sound.
5. Speedometer
Indicates vehicle speed.
6. Front Axle Lock Indicator Light — If Equipped Indicates when the front axle lock has been
activated.
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7. Seat Belt Indicator LightA warning chime and an indicator light will alert
you to buckle the seat belts. When the belt is
buckled, the chime will stop, but the light will stay
on until it times out (about six seconds).
8. Turn Signal Indicator Lights The arrows will flash with the exterior turn signals
when the turn signal lever is operated. A tone will
chime if the turn signals are left on for more than 1 mi (2
km).
9. Oil Pressure Warning Light Shows low engine oil pressure. The light will come
on and remain on when the ignition switch is
turned from the OFF to the ON position, and the light
will turn off after the engine is started. If the bulb does
not come on, have the system checked by your autho-
rized dealer. If the warning light comes on and remains on while
driving, stop the vehicle and shut off the engine. DO
NOT OPERATE THE VEHICLE UNTIL THE CAUSE IS
CORRECTED. Also, a single chime will sound.
10. High Beam Indicator Light
This light shows that the headlights are on high
beam. Push the multifunction control lever away
from you to switch the headlights to high beam. Pull the
lever towards you to switch the headlights back to low
beam. If the driver’s door is open, and the headlights or
park lights are left on, the High Beam Indicator Light will
remain illuminated and a chime will sound.
11. Brake Warning Light After the ignition is turned on, this light illumi-
nates to indicate function check at vehicle start-
up. It also indicates if the parking brake is
applied. If the light stays on when the parking brake is
UNDERSTANDING YOUR INSTRUMENT PANEL 207
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U.S. federal regulations require that upon transfer of
vehicle ownership, the seller certify to the purchaser the
correct mileage that the vehicle has been driven. There-
fore, if the odometer reading is changed during repair or
replacement, be sure to keep a record of the reading
before and after the service so the correct mileage can be
determined.
Vehicle Warning Messages
When the appropriate conditions exist, messages such as
“door” (indicates that a door(s) may be ajar), “gATE” (if
the swing gate is open or ajar), “gASCAP” (which
indicates that your gas cap is possibly loose or damaged),
CHANgE OIL” (indicates that the engine oil should be
changed), “ESPOFF” (indicates that ESP is turned off),
and “noFUSE” (indicates that the Ignition Off Draw
(IOD) fuse is removed from the Integrated Power Mod-
ule), will display in the odometer.Change Oil Message
Your vehicle is equipped with an engine oil change
indicator system. The “CHANgE OIL” message will flash
in the instrument cluster odometer for approximately 12
seconds after a single chime has sounded to indicate the
next scheduled oil change interval. The engine oil change
indicator system is duty-cycle based, which means the
engine oil change interval may fluctuate dependent upon
your personal driving style.
Unless reset, this message will continue to display each
time you turn the ignition switch to the ON/RUN
position. To turn off the message temporarily, press and
release the Trip Odometer button on the instrument
cluster. To reset the oil change indicator system (after
performing the scheduled maintenance) refer to the fol-
lowing procedure.
1. Turn the ignition switch to the ON position (Do not
start the engine).
212 UNDERSTANDING YOUR INSTRUMENT PANEL

2. Fully depress the accelerator pedal slowly three
times within 10 seconds.
3. Turn the ignition switch to the OFF/LOCK position.
NOTE: If the indicator message illuminates when you
start the vehicle, the oil change indicator system did not
reset. If necessary repeat this procedure.
25. Malfunction Indicator Light This light is a part of an Onboard Diagnostic
System called OBD II that monitors engine and
automatic transmission control systems. The light
will illuminate when the ignition is in the ON position
before engine start. If the bulb does not come on when
turning the key from OFF to ON, have the condition
checked promptly.
Certain conditions such as a loose or missing gas cap,
poor quality fuel, etc. may illuminate the light after
engine start. The vehicle should be serviced if the light stays on through several typical driving styles. In most
situations, the vehicle will drive normally and will not
require towing.
When the engine is running, the Malfunction Indicator
Light may flash to alert serious conditions that could lead
to immediate loss of power or severe catalytic converter
damage. The vehicle should be serviced as soon as
possible if this occurs.
26. Electronic Stability Program (ESP) Indicator
Light/Traction Control System (TCS) Indicator Light
This indicator light starts to flash as soon as the
tires lose traction and the ESP system becomes
active. The ESP/TCS Indicator Light also
flashes when TCS is active. If the ESP/TCS
Indicator Light begins to flash during acceleration, ease
up on the accelerator and apply as little throttle as
possible. Be sure to adapt your speed and driving to the
prevailing road conditions. The ESP/TCS Indicator Light
UNDERSTANDING YOUR INSTRUMENT PANEL 213
4

Regular cleaning of the inside of the windows with a
non-filming cleaning solution (vinegar and water works
very well) will help prevent contaminates (cigarette
smoke, perfumes, etc.) from sticking to the windows.
Contaminates increase the rate of window fogging.
Summer Operation
Air conditioned vehicles must be protected with a high
quality antifreeze coolant during summer to provide
proper corrosion protection and to raise the boiling point
of the coolant for protection against overheating. A 50 %
concentration is recommended. Refer to Fluids and
Genuine Parts in Section 7 for the proper coolant type.
When using the air conditioner in extremely heavy traffic
in hot weather especially when towing a trailer, addi-
tional engine cooling may be required. If this situation is
encountered, operate the transmission in a lower gear to
increase engine RPM, coolant flow and fan speed. When
stopped in heavy traffic, it may be necessary to shift intoNEUTRAL (N) and depress the accelerator slightly for
fast idle operation to increase coolant flow and fan speed.
Winter Operation
When operating the system during the winter months,
make sure the air intake, located directly in front of the
windshield, is free of ice, slush, snow, or other obstruc-
tions.
Vacation Storage
Anytime you store your vehicle, or keep it out of service
(i.e., vacation) for two weeks or more, run the air
conditioning system at idle for about five minutes in the
fresh air and high blower setting. This will ensure
adequate system lubrication to minimize the possibility
of compressor damage when the system is started again.
266 UNDERSTANDING YOUR INSTRUMENT PANEL

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.
STARTING AND OPERATING 303
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MAINTAINING YOUR VEHICLE
CONTENTS
Engine Compartment – 3.8L ...............378
 Onboard Diagnostic System — OBD II ........379
▫ Loose Fuel Filler Cap Message ............380
 Emissions Inspection And Maintenance
Programs ............................380
 Replacement Parts ......................382
 Authorized Dealer Service ................382
 Maintenance Procedures ..................383
▫ Engine Oil ..........................383 ▫
Drive Belts — Check Condition And Tension . . 386
▫ Spark Plugs .........................386
▫ Catalytic Converter ....................386
▫ Crankcase Emission Control System ........388
▫ Fuel Filter ..........................388
▫ Engine Air Cleaner Filter ................389
▫ Maintenance-Free Battery ................389
▫ Air Conditioner Maintenance .............390
▫ Power Steering Fluid Check ..............391
7

MAINTENANCE PROCEDURES
The pages that follow contain therequiredmaintenance
services determined by the engineers who designed your
vehicle.
Besides the maintenance items for which there are fixed
maintenance intervals, there are other items that should
operate satisfactorily without periodic maintenance.
However, if a malfunction of these items does occur, it
could adversely affect the engine or vehicle performance.
These items should be inspected if a malfunction is
observed or suspected.
Engine Oil
Checking Oil Level
To assure proper lubrication of your vehicle’s engine, the
engine oil must be maintained at the correct level. The
best time to check the engine oil level is about five
minutes after a fully warmed up engine is shut off or
before starting the engine after it has sat overnight. Checking the oil while the vehicle is on level ground will
improve the accuracy of the oil level readings. Always
maintain the oil level within the SAFE zone on the
dipstick. Adding 1 U.S. Quart (0.95L) of oil when the
reading is at the bottom of the SAFE zone will result in a
reading at the top of the safe zone on these engines.
MAINTAINING YOUR VEHICLE 383
7

CAUTION!
Overfilling or underfilling the crankcase will cause
aeration or loss of oil pressure. This could damage
your engine.
Change Engine Oil
Refer to the Maintenance Schedule in Section 8 for
recommended engine oil change intervals.
Engine Oil Selection
For best performance and maximum protection for all
engines under all types of operating conditions, the
manufacturer recommends engine oils that are API Cer-
tified and meet the requirements of DaimlerChrysler
Material Standard MS-6395.
American Petroleum Institute (API) Engine Oil
Identification Symbol
This symbol means that the oil has
been certified by the American
Petroleum Institute (API). The
manufacturer only recommends
API Certified engine oils.
Engine Oil Viscosity (3.8L Engines)
SAE 5W-20 engine oil is recommended for all operating
temperatures. This engine oil improves low temperature
starting and vehicle fuel economy.
The engine oil filler cap also shows the recommended
engine oil viscosity for your engine. For information on
engine oil filler cap location, refer to the “Engine Com-
partment” illustration in this section.
384 MAINTAINING YOUR VEHICLE