2008 JEEP COMMANDER light

in the EVIC, and the graphic display will still show the
low tire pressure value flashing. Driving the vehicle for
up to 10 minutes above 15 mph (24 km/h) will turn OFF
the ªTire Pressure Monitoring Telltale Lightº as long as
none of road tires are below the low pressure warning
threshold. The EVIC will also display a ªSpare Low
Pressureº text message, and the graphic display will
show a tire pressure value in place of the flashing low tire
pressure value.
NOTE:If your vehicle is not equipped with a matching
full size spare wheel and tire assembly, it does not have a
tire pressure monitoring sensor in the spare tire. The
TPMS will not be able to monitor the tire pressure. If you
install the spare tire in place of a road tire that has a
pressure below the low-pressure warning limit, upon the
next ignition key cycle, the ªTire Pressure Monitoring
Telltale Lightº will remain ON, a chime will sound, and
the EVIC will still display a flashing pressure value in the
graphic display. After driving the vehicle for up to 10minutes above 15 mph (24 km/h), the ªTire Pressure
Monitoring Telltale Lightº will flash on and off for 75
seconds and then remain on solid. In addition, the EVIC
will display a9CHECK TPM SYSTEM9message for 3
seconds and then display dashes (- -) in place of the
pressure value. For each subsequent ignition key cycle, a
chime will sound, the ªTire Pressure Monitoring Telltale
Lightº will flash on and off for 75 seconds and then
remain on solid, and the EVIC will display a9CHECK
TPM SYSTEM9message for 3 seconds and then display
dashes (- -) in place of the pressure value. Once you
repair or replace the original road tire, and reinstall it on
the vehicle in place of the spare tire, the TPMS will
update automatically.
In addition, the ªTire Pressure Monitoring Telltale Lightº
will turn OFF and the graphic in the EVIC will display a
new pressure value instead of dashes (- -), as long as no
tire pressure is below the low-pressure warning limit in
any of the four active road tires. The vehicle may need to
332 STARTING AND OPERATING

using high quality unleaded gasoline having an octane
range of 87 to 89. The manufacturer recommends the use
of 89 octane for optimum performance. 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 and mid-grade gaso-
lines, and in some circumstances 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 world wide 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 ªReformulated Gasoline.º
Reformulated gasoline contains oxygenates, and are spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.
The manufacturer supports the use of reformulated gaso-
line. Properly blended reformulated gasoline will pro-
vide excellent performance and durability of engine and
fuel system components.
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Materials Added To Fuel
All gasoline sold in the United States is required to
contain effective detergent additives. Use of additional
detergents or other additives is not needed under normal
conditions and would result in additional cost. Therefore
you should not have to add anything to the fuel.
Fuel System Cautions
CAUTION!
Follow these guidelines to maintain your vehicle's
performance:
²The use of leaded gas is prohibited by Federal law.
Using leaded gasoline can impair engine performance,
damage the emission control system.
²An out-of-tune engine, or certain fuel or ignition
malfunctions, can cause the catalytic converter to
overheat. If you notice a pungent burning odor or
some light smoke, your engine may be out of tune or
malfunctioning and may require immediate service.
Contact your dealer for service assistance.
²The use of fuel additives which are now being sold as
octane enhancers is not recommended. Most of these
products contain high concentrations of methanol.
Fuel system damage or vehicle performance problems
resulting from the use of such fuels or additives is not
the responsibility of the manufacturer.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
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CAUTION!
Damage to the fuel system or emission control sys-
tem could result from using an improper fuel cap
(gas cap). A poorly fitting cap could let impurities
into the fuel system. Also, a poorly fitting after-
market cap can cause the MIL (Malfunction Indicator
Light) to illuminate, due to fuel vapors escaping from
the system.
CAUTION!
A poorly fitting gas cap may cause the Malfunction
Indicator Light to turn on.
CAUTION!
To avoid fuel spillage and overfilling, do not ªtop
offº the fuel tank after filling.
NOTE:When the fuel nozzle ªclicksº or shuts off, the
fuel tank is full.
WARNING!
²Never have any smoking materials lit in or near
the vehicle when the gas cap is removed or the
tank filled.
²Never add fuel when the engine is running. This is
in violation of most state and federal fire regula-
tions and will cause the malfunction indicator
light to turn on.
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NOTE:Tighten the gas cap about 1/4 turn until you
hear one click. This is an indication that cap is properly
tightened.
If the gas cap is not tighten properly, the Malfunction
Indicator Light will come on. Be sure the gas cap is
tightened every time the vehicle is refueled.
Loose Fuel Filler Cap Message
If the vehicle diagnostic system determines that the fuel
filler cap is loose, improperly installed, or damaged, a
ªCHECK GASCAPº message will be displayed in the
EVIC (Electronic Vehicle Information Center). Refer to
ªElectronic Vehicle Information Centerº in Section 4 of
this manual. Tighten the fuel filler cap until a ªclickingº
sound is heard. This is an indication that the fuel filler
cap is properly tightened. Refer to ªOnboard Diagnostic
System Ð OBDIIº in Section 7 of this manual for more
information.
WARNING!
A fire may result if gasoline is pumped into a
portable container that is inside of a vehicle. You
could be burned. Always place gas containers on the
ground while filling.
CAUTION!
Damage to the fuel system or emission control sys-
tem could result from using an improper fuel tank
filler cap (gas cap). A poorly fitting cap could let
impurities into the fuel system.
STARTING AND OPERATING 343
5

Trailer Hitch Classification
Your vehicle may be factory equipped for safe towing of
trailers weighing over 3,500 lbs (1 587 kg) with the
optional Trailer Tow Prep Package. See your dealer for
package content.
The following chart provides the industry standard for
the maximum trailer weight a given trailer hitch class can
tow and should be used to assist you in selecting the
correct trailer hitch for your intended towing condition.
Refer to the Trailer Towing Weights (Maximum Trailer
Weight Ratings) chart for the Max. GTW towable for your
given drivetrain.Trailer Hitch Classification
Class Max. GTW
(Gross Trailer Wt.)
Class I - Light Duty 2,000 lbs (907 kg)
Class II - Medium
Duty3,500 lbs (1 587 kg)
Class III - Heavy Duty 5,000 lbs (2 268 kg)
Class IV - Extra
Heavy Duty10,000 lbs (4 540 kg)
All trailer hitches should be professionally installed on
your vehicle.
Trailer Towing Weights (Maximum Trailer Weight
Ratings)
The following chart provides the maximum trailer
weight ratings towable for your given drivetrain.
350 STARTING AND OPERATING

actuated brakes. When towing a trailer equipped with
a hydraulic surge actuated brake system, an electronic
brake controller is not required.
þTrailer brakes are recommended for trailers over 1,000
lbs (454 kg) and required for trailers in excess of 2,000
lbs (907 kg).
CAUTION!
If the trailer weighs more than 1,000 lbs (454 kg)
loaded, it should have its own brakes and they
should be of adequate capacity. Failure to do this
could lead to accelerated brake lining wear, higher
brake pedal effort, and longer stopping distances.
WARNING!
Do not connect trailer brakes to your vehicle's hy-
draulic brake lines. It can overload your brake sys-
tem and cause it to fail. You might not have brakes
when you need them and could have an accident.
Towing any trailer will increase your stopping dis-
tance. When towing you should allow for additional
space between your vehicle and the vehicle in front
of you. Failure to do so could result in an accident.
Towing Requirements Ð Trailer Lights & Wiring
Whenever you pull a trailer, regardless of the trailer size,
stop lights and turn signals on the trailer are required for
motoring safety.
356 STARTING AND OPERATING

Towing Tips Ð Automatic Transmission
The ªDº range can be selected when towing. However, if
frequent shifting occurs while in this range, the ºTow/
Haulº mode (if equipped) or a lower gear range should
be selected.
NOTE:Using the ºTow/Haulº mode (if equipped) or a
lower gear range while operating the vehicle under
heavy operating conditions will improve performance
and extend transmission life by reducing excessive shift-
ing 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 ªMain-
tenance Scheduleº in Section 8 of this manual for trans-
mission fluid change intervals.
NOTE:Check the automatic transmission fluid level
before towing.
Towing Tips Ð Electronic Speed Control (If
Equipped)
þ
Don't use in hilly terrain or with heavy loads.
þWhen 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.
þUse speed control in flat terrain and with light loads to
maximize fuel efficiency.
Towing Tips Ð Cooling System
To reduce potential for engine and transmission over-
heating, take the following actions:
þCity Driving
When stopped for short periods of time, put transmission
in N (Neutral) and increase engine idle speed.
þHighway Driving
Reduce speed.
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