2007 JEEP GRAND CHEROKEE service

build up between the tire tread and the road. This
hydroplaning action can cause loss of traction, braking
ability, and control.
•After going through deep water or a car wash, brakes
may become wet, resulting in decreased performance
and unpredictable braking action. Dry the brakes by
gentle, intermittent pedal action while driving at very
slow speeds.
POWER STEERING
The standard power steering system will give you good
vehicle response and increased ease of maneuverability
in tight spaces. The system will provide mechanical
steering capability if power assist is lost.
If for some reason the power assist is interrupted, it will
still be possible to steer your vehicle. Under these condi-
tions, you will observe a substantial increase in steering
effort, especially at very low vehicle speeds and during
parking maneuvers.NOTE:Increased noise levels at the end of the steering
wheel travel are considered normal and do not indicate
that there is a problem with the power steering system.
Upon initial start-up in cold weather, the power steering
pump may make noise for a short amount of time. This is
due to the cold, thick fluid in the steering system. This
noise should be considered normal, and does not in any
way damage the steering system.WARNING!
Continued operation with reduced power steering
assist could pose a safety risk to yourself and others.
Service should be obtained as soon as possible.
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EXAMPLE:
Service Description:
95= Load Index
—A numerical code associated with the maximum load a tire can carry.
H= Speed Symbol
—A symbol indicating the range of speeds at which a tire can carry a load corresponding
to its load index under certain operating conditions.
—The maximum speed corresponding to the Speed Symbol should only be achieved un-
der specified operating conditions. (i.e. tire pressure, vehicle loading, road conditions,
and posted speed limits).
Load Identification:
....blank....= Absence of any text on sidewall of the tire indicates a Standard Load (SL) Tire
Extra Load (XL)= Extra Load (or Reinforced) Tire
Light Load= Light Load Tire
C,D,E= Load range associated with the maximum load a tire can carry at a specified pressure
Maximum Load— Maximum Load indicates the maximum load this tire is designed to carry.
Maximum Pressure—
Maximum Pressure indicates the maximum permissible cold tire inflation pressure for this tire.
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Life of Tire
The service life of a tire is dependent upon varying
factors including but not limited to:
•Driving style
•Tire pressure
•Distance driven
WARNING!
Tires and spare tire should be replaced after six
years, regardless of the remaining tread. Failure to
follow this warning can result in sudden tire failure.
You could lose control and have an accident result-
ing in serious injury or death.
Keep unmounted tires in a cool, dry place with as little
exposure to light as possible. Protect tires from contact
with oil, grease and gasoline.
Replacement Tires
The tires on your new vehicle provide a balance of many
characteristics. They should be inspected regularly for
wear and correct cold tire inflation pressure. The manu-
facturer strongly recommends that you use tires equiva-
lent to the originals in size, quality and performance
when replacement is needed (see the paragraph on tread
wear indicators). Refer to the Tire and Loading Informa-
tion placard for the size designation of your tire. The
service description and load identification will be found
on the original equipment tire. Failure to use equivalent
replacement tires may adversely affect the safety, han-
dling, and ride of your vehicle. We recommend that you
contact your original equipment or an authorized tire
dealer with any questions you may have on tire specifi-
cations or capability.
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Should a low tire condition occur on any of the four
active road tire(s), you should stop as soon as possible,
and inflate the low tire(s) that is flashing on the graphic
display to the vehicle’s recommended cold tire pressure.
The system will automatically update, the graphic dis-
play of the pressure value(s) will stop flashing, and the
“Tire Pressure Monitoring Telltale Light” will extinguish
once the updated tire pressure(s) have been received. The
vehicle may need to be driven for up to 10 minutes above
15 mph (24 km/h) to receive this information.
Service Tire Pressure System
The “Tire Pressure Monitoring Telltale Light” will flash
on and off for 60 seconds, and an audible chime will
sound when a system fault is detected. The flash cycle
will repeat every ten minutes, without an audible chime,
until the fault condition no longer exists.
The EVIC will display the “SERVICE TIRE PRESS. SYS-
TEM” message for 3 seconds. This text message is thenfollowed by a graphic, with “- -“ displayed for the
pressure value(s) indicating which of the Tire Pressure
Monitoring Sensor(s) is not being received. Refer to
“Electronic Vehicle Information Center (EVIC)” in Sec-
tion 4 of this manual.
NOTE:Your system can be set to display pressure units
in PSI, kPa, or BAR.
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If the ignition key is cycled, this sequence will repeat,
providing the system fault still exists. If the system fault
no longer exists, the “Tire Pressure Monitoring Telltale
Light” will no longer flash, theSERVICE TIRE PRESS.
SYSTEMtext message will no longer display, and a
pressure value will be displayed instead of dashes.
NOTE:If your vehicle is equipped with a matching full
size spare tire, 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, a chime to sound, a
Low Pressure message to appear 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 “Tire Pressure
Monitoring Telltale Light” as long as the matching full
size spare tire or any other road tire(s) are not below thelow pressure warning threshold. The EVIC will display a
“Spare Low Pressure” text message, and the graphic
display will show a new tire pressure value in place of
the flashing low tire pressure value.
NOTE:If your vehicle is equipped with a non-matching
full size spare tire, it does not have a tire pressure
monitoring sensor. Therefore, it will not be monitored by
the Tire Pressure Monitor System (TPMS). In the event
that the non-matching full size spare tire is swapped with
a low pressure road tire, every ignition key cycle will still
show the “Tire Pressure Monitoring Telltale Light” to be
ON, a chime to sound, a Low Pressure message to appear
in the EVIC, and the graphic display will still show the
low tire pressure value flashing. After the original road
tire has been properly repaired and put back onto the
vehicle in place of the non-matching full size spare tire,
the TPMS will update the graphic display on the EVIC
with a new tire pressure value instead of the flashing low
tire pressure value, and the “Tire Pressure Monitoring
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5.7L Engines (If Equipped)
The 5.7L engine is designed to meet all
emissions regulations and provide satisfac-
tory fuel economy and performance when
using high quality unleaded gasoline hav-
ing an octane range of 87 to 89. The manu-
facturer 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 gasolines, 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 “Reformulated Gasoline”.
Reformulated gasolines contain oxygenates, and are spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.
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It is even more important to look for gasolines without
MMT in Canada, because MMT can be used at levels
higher than those allowed in the United States.
MMT is prohibited in Federal and California reformu-
lated gasoline.
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:
•The use of leaded gas is prohibited by Federal law.
Using leaded gasoline can impair engine performance,
damage the emission control system.
•An 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.
•The 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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NOTE:When the ambient temperature is above 90°F
(32°C), you may experience hard starting and rough idle
following start up even if the above recommendations are
followed.
Selection Of Engine Oil For Flexible Fuel Vehicles
(E-85) and Gasoline Vehicles
Whether operating the vehicle on an E-85 ethanol fuel or
unleaded gasoline the engine oil requirements are the
same. Refer to “Maintenance Procedures” in Section 7 of
this manual for the proper quality and viscosity engine
oil.
Starting
The characteristics of E-85 fuel make it unsuitable for use
when ambient temperatures fall below 0°F (-18°C). In the
range of 0°F (-18°C) to 32°F (0°C), you may experience an
increase in the time it takes for your engine to start, and
a deterioration in drivability (sags and/or hesitations)
until the engine is fully warmed up.
Cruising Range
Because E-85 fuel contains less energy per gallon than
gasoline, you will experience an increase in fuel con-
sumption. You can expect your miles per gallon (mpg)
and your driving range to decrease by about 30% com-
pared to gasoline operation.
Replacement Parts
Many components in your Flexible Fuel Vehicle (FFV) are
designed to be compatible with ethanol. Always be sure
that your vehicle is serviced with correct ethanol com-
patible parts.
CAUTION!
Replacing fuel system components with non-ethanol
compatible components can damage your vehicle.
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