2008 JEEP WRANGLER gas mileage

If any other active warnings including “gATE”, “gAS-
CAP”, “noFUSE”, “CHANgE OIL”, or “ESPOFF” are
present, they will be shown in the VF display and will
also continue to cycle. If the vehicle is moving, three
single chimes will occur, one chime for each complete
display cycle (three cycles total). After this, the display
will continue to cycle only (no chimes).
If the trip/reset button is pressed while the VF warnings
are being displayed, the VF display will revert back to
only displaying the odometer/trip odometer mileage.
Upper Half Door Window Removal (If Equipped)
1. Grasp the half door window and pull up.Upper Half Door Window Installation (If
Equipped)
1. Grasp the half door window and line up pins into
pockets in lower door.
Upper Half Door Window
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DOOR LOCKS
The vacuum fluorescent (VF) display located in the
odometer area displays the word “door” as an indication
of a door ajar or door not completely closed. When the
vehicle is not moving and the door is ajar or not
completely closed, the VF display will show the word
“door.”
If any other active warnings including “gATE”, “gAS-
CAP”, “noFUSE”, “CHANgE OIL”, or “ESPOFF” are
present, they will be shown in the VF display and will
also continue to cycle. If the vehicle is moving, three
single chimes will occur, one chime for each complete
display cycle (three cycles total). After this, the display
will continue to cycle only (no chimes).If the trip/reset button is pressed while the VF warnings
are being displayed, the VF display will revert back to
only displaying the odometer/trip odometer mileage.
NOTE:
The ignition key that is used to start the vehicle
is used to lock or unlock the doors, swing gate, and
console storage.
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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

Drive Belts — Check Condition and Tension
Belt tension is controlled by means of an automatic
tensioner. No belt tension adjustments are required.
However, belt and belt tensioner condition should be
inspected at the specified intervals, and replaced if re-
quired. See your authorized dealer for service
At the mileage indicated in the Maintenance Schedule,
the condition of all the belts and tensioner should be
checked. Refer to Section 8 of this manual. Improper belt
tension can cause belt slippage and failure.
Belts should be inspected for evidence of cuts, cracks,
glazing, or frayed cords and replaced if there is indication
of damage, which could result in belt failure. Low
generator belt tension can cause battery failure.
Also, check belt routing to make sure there is no inter-
ference between the belts and other engine components.
Spark Plugs
Spark plugs must fire properly to assure engine perfor-
mance and emission control. New plugs should be in-
stalled at the mileage specified in the Maintenance Sched-
ule. Refer to Section 8 of this manual. The entire set
should be replaced if there is any malfunction due to a
faulty spark plug. Refer to Fluids, Lubricants, and Genu-
ine Parts in this section for spark plug information.
Catalytic Converter
The catalytic converter requires the use of unleaded fuel
only. Leaded gasoline will destroy the effectiveness of the
converter as an emission control device.
Under normal operating conditions, the catalytic con-
verter will not require maintenance. However, it is im-
portant to keep the engine properly tuned to assure
proper catalyst operation and prevent possible catalyst
damage.
386 MAINTAINING YOUR VEHICLE

ONLY the correct type thermostat. Other designs may
result in unsatisfactory cooling performance, poor gas
mileage, and increased emissions.
Hoses and Vacuum/Vapor Harnesses
Inspect surfaces of hoses and nylon tubing for evidence
of heat and mechanical damage. Hard or soft spots,
brittle rubber, cracking, tears, cuts, abrasions, and exces-
sive swelling indicate deterioration of the rubber.
Pay particular attention to the hoses nearest to high heat
sources such as the exhaust manifold. Inspect hose rout-
ing to be sure hoses do not touch any heat source or
moving component that may cause heat damage or
mechanical wear.
Ensure nylon tubing in these areas has not melted or
collapsed. Inspect all hose connections such as clamps
and couplings to make sure they are secure and no leaksare present. Components should be replaced immedi-
ately if there is any evidence of degradation that could
cause failure.
Brake System
In order to assure brake system performance, all brake
system components should be inspected periodically.
Refer to the Maintenance Schedule in Section 8 for
suggested service intervals.
WARNING!
Riding the brakes can lead to brake failure and
possibly an accident. Driving with your foot resting
or riding on the brake pedal can result in abnormally
high brake temperatures, excessive lining wear, and
possible brake damage. You wouldn’t have your full
braking capacity in an emergency.
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