2007 JEEP GRAND CHEROKEE maintenance

▫Alignment And Balance.................293

Tire Chains...........................294

Tire Rotation Recommendations............294

Tire Pressure Monitor System (TPMS)........295
▫Base System — If Equipped..............297
▫Premium System — If Equipped..........300
▫General Information...................305

Fuel Requirements......................305
▫3.7/4.7L Engines (If Equipped)............305
▫5.7L Engines (If Equipped)...............306
▫Reformulated Gasoline.................306
▫Gasoline/Oxygenate Blends..............307
▫MMT In Gasoline.....................307▫Materials Added To Fuel................308
▫Fuel System Cautions..................308
▫Carbon Monoxide Warnings..............309

Flexible Fuel (4.7L Only) — If Equipped......309
▫E-85 General Information................309
▫Ethanol Fuel (E-85)....................310
▫Fuel Requirements....................310
▫Selection Of Engine Oil For Flexible Fuel Vehicles
(E-85) And Gasoline Vehicles.............311
▫Starting............................311
▫Cruising Range.......................311
▫Replacement Parts.....................311
▫Maintenance.........................312
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CAUTION!
When driving through water, do not exceed 5 mph (8
km/h). Always check water depth before entering as
a precaution, and check all fluids afterward. Driving
through water may cause damage that may not be
covered by the new vehicle limited warranty.
Driving through water more than a few inches deep will
require extra caution to ensure safety and prevent dam-
age to your vehicle. If you must drive through water, try
to determine the depth and the bottom condition (and
location of any obstacles) prior to entering. Proceed with
caution and maintain a steady controlled speed less than
5 mph (8 km/h) in deep water to minimize wave effects.
Flowing Water
If the water is swift flowing and rising (as in storm
run-off) avoid crossing until the water level recedesand/or the flow rate is reduced. If you must cross
flowing water avoid depths in excess of 9 inches. The
flowing water can erode the streambed causing your
vehicle to sink into deeper water. Determine exit point(s)
that are downstream of your entry point to allow for
drifting.
Standing Water
Avoid driving in standing water deeper than 20 inches,
and reduce speed appropriately to minimize wave ef-
fects. Maximum speed in 20 inches of water is less than 5
mph (8 km/h).
Maintenance
After driving through deep water, inspect your vehicle
fluids and lubricants (engine oil, transmission oil, axle,
transfer case) to assure the fluids have not been contami-
nated. Contaminated fluid (milky, foamy in appearance)
should be flushed/changed as soon as possible to pre-
vent component damage.
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Follow the recommended tire rotation frequency for your
type of driving found in the “Maintenance Schedules”
Section of this manual. More frequent rotation is permis-
sible if desired. The reasons for any rapid or unusual
wear should be corrected prior to rotation being per-
formed.
NOTE:The Premium Tire Pressure Monitor System will
automatically locate the pressure values displayed in the
correct vehicle position following a tire rotation.
The suggested rotation method is the “forward-cross”
shown in the following diagram.
TIRE PRESSURE MONITOR SYSTEM (TPMS)
The Tire Pressure Monitoring System (TPMS) will warn
the driver of a low tire pressure based on the vehicle
recommended cold tire pressure.
The tire pressure will vary with temperature by about 1
psi (7 kPa) for every 12°F (–11°C). This means that when
the outside temperature decreases, the tire pressure will
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will update automatically, and the “Tire Pressure Moni-
toring Telltale Light” will be OFF as long as none of the
road tires are below the low pressure warning threshold.
The vehicle may need to be driven for up to 10 minutes
above 15 mph (24 km/h) to receive this information.
CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures have
been established for the tire size equipped on your
vehicle. Undesirable system operation or sensor
damage may result when using replacement equip-
ment that is not of the same size, type, and/or style.
After-market wheels can cause sensor damage. Do
not use tire sealant from a can, or balance beads if
your vehicle is equipped with a TPMS, as damage to
the sensors may result.
CAUTION!
After inspecting or adjusting the tire pressure al-
ways reinstall the valve stem cap. This will prevent
moisture and dirt from entering the valve stem,
which could damage the Tire Pressure Monitoring
Sensor.
NOTE:
•The TPMS is not intended to replace normal tire care
and maintenance, or to provide warning of a tire
failure or condition.
•The TPMS should not be used as a tire pressure gauge
while adjusting your tire pressure.
•Driving on a significantly under-inflated tire causes
the tire to overheat and can lead to tire failure.
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Telltale Light” will be OFF as long as no road tire(s) are
below the low pressure warning threshold. The vehicle
may need to be driven for up to 10 minutes above 15 mph
(24 km/h) to receive this information.
CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures have
been established for the tire size equipped on your
vehicle. Undesirable system operation or sensor
damage may result when using replacement equip-
ment that is not of the same size, type, and/or style.
After-market wheels can cause sensor damage. Do
not use tire sealant from a can, or balance beads if
your vehicle is equipped with a TPMS, as damage to
the sensors may result.
CAUTION!
After inspecting or adjusting the tire pressure al-
ways reinstall the valve stem cap. This will prevent
moisture and dirt from entering the valve stem,
which could damage the Tire Pressure Monitoring
Sensor.
NOTE:
•The TPMS is not intended to replace normal tire care
and maintenance, nor to provide warning of a tire
failure or condition.
•The TPMS should not be used as a tire pressure gauge
while adjusting your tire pressure.
•Driving on a significantly under-inflated tire causes
the tire to overheat and can lead to tire failure.
304 STARTING AND OPERATING

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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Maintenance
If you operate the vehicle using E-85 fuel, follow “Main-
tenance Schedule B.” Refer to Section 8 of this manual.
CAUTION!
Do not use ethanol mixture greater than 85% in your
vehicle. It will cause difficulty in cold starting and
may affect driveability.
FUEL REQUIREMENTS — DIESEL
Diesel fuels are available from most reputable fuel mar-
keters. We encourage you to use only the best quality fuel
with a calculated Cetane Index of 50 or higher. In
addition, the manufacturer recommends using diesel fuel
with a sulfur content ofless than 15 ppm.See your
authorized dealer or distributor for further information
regarding fuels available in your area.In areas where diesel fuel is below the recommended
quality levels (high levels of sulfur and water) it is critical
to monitor the fuel filter for contamination and the
“Water-In-Fuel” message in the EVIC (Refer to Section 4).
Failure to properly service the fuel system for these items
can significantly reduce engine life and lead to major
engine repair. More frequent service intervals of the fuel
filter/water separator unit may be required under these
conditions than those shown in “Maintenance Schedule
A or B.” See your authorized dealer or distributor for
specific information.
312 STARTING AND OPERATING

NOTE:Remember that everything put into or on the
trailer adds to the load on your vehicle. Also, additional
factory-installed options, or dealer-installed options,
must be considered as part of the total load on your
vehicle. Refer to the Tire and Loading Information plac-
ard in the Tire Safety Information section of this manual
for the maximum combined weight of occupants and
cargo for your vehicle.
Towing Requirements
To promote proper break-in of your new vehicle drivetrain
components the following guidelines are recommended:
CAUTION!
•Avoid towing a trailer for the first 500 miles (805 km)
of vehicle operation. Doing so may damage your
vehicle.
•During the first 500 miles (805 km) of trailer towing,
limit your speed to 50 mph (80 km/h).
Perform the maintenance listed in Section 8 of this
manual. When towing a trailer, never exceed the GAWR,
or GCWR, ratings.
WARNING!
Improper towing can lead to an injury accident.
Follow these guidelines to make your trailer towing
as safe as possible:
Make certain that the load is secured in the trailer
and will not shift during travel. When trailering
cargo that is not fully secured, dynamic load shifts
can occur that may be difficult for the driver to
control. You could lose control of your vehicle and
have an accident.
•When hauling cargo or towing a trailer, do not over-
load your vehicle or trailer. Overloading can cause a
326 STARTING AND OPERATING