2008 JEEP GRAND CHEROKEE engine

Over 40 auto manufacturers worldwide have issued and
endorsed consistent gasoline specifications (the World-
wide Fuel Charter, WWFC) which 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 gasolines contain oxygenates, and are spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.
The manufacturer supports the use of reformulated gaso-
lines. Properly blended reformulated gasolines will pro-
vide excellent performance and durability of engine and
fuel system components.
Gasoline/Oxygenate Blends
Some fuel suppliers blend unleaded gasoline with oxy-
genates such as 10% ethanol, MTBE, and ETBE. Oxygen-
ates are required in some areas of the country during the
winter months to reduce carbon monoxide emissions.
Fuels blended with these oxygenates may be used in
your vehicle.
CAUTION!
DO NOT use gasolines containing Methanol or E85
Ethanol. Use of these blends may result in starting
and driveability problems and may damage critical
fuel system components.
Problems that result from using methanol/gasoline or
E85 Ethanol blends are not the responsibility of the
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manufacturer. While MTBE is an oxygenate made from
Methanol, it does not have the negative effects of Metha-
nol.
MMT In Gasoline
MMT is a manganese containing metallic additive that is
blended into some gasoline to increase octane. Gasoline
blended with MMT provides no performance advantage
beyond gasoline of the same octane number without
MMT. Gasoline blended with MMT reduces spark plug
life and reduces emission system performance in some
vehicles. The manufacturer recommends that gasoline
without MMT be used in your vehicle. The MMT content
of gasoline may not be indicated on the gasoline pump;
therefore, you should ask your gasoline retailer whether
his/her gasoline contains MMT. It is even more impor-
tant 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 reformulated 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 they 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,
and damage the emission control system.
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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.
Carbon Monoxide Warnings
WARNING!
Carbon monoxide (CO) in exhaust gases is deadly.
Follow the precautions below to prevent carbon
monoxide poisoning:
²Do not inhale exhaust gases. They contain carbon
monoxide, a colorless and odorless gas, which can kill.
Never run the engine in a closed area, such as a
garage, and never sit in a parked vehicle with the
engine running for an extended period. If the vehicle is
stopped in an open area with the engine running for
more than a short period, adjust the ventilation system
to force fresh, outside air into the vehicle.
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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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WARNING!
²Never add fuel when the engine is running.
²Never have any smoking materials lit in or near
the vehicle when the fuel cap is removed or the
tank filled.
TRAILER TOWING
In this section you will find safety tips and information
on limits to the type of towing you can reasonably do
with your vehicle. Before towing a trailer carefully re-
view this information to tow your load as efficiently and
safely as possible.
To maintain warranty coverage, follow the requirements
and recommendations in this manual concerning ve-
hicles used for trailer towing.
Common Towing Definitions
The following trailer towing related definitions will assist
you in understanding the following information:
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total allowable weight of your vehicle.
This includes driver, passengers, cargo and tongue
weight. The total load must be limited so that you do not
exceed the GVWR.
Gross Trailer Weight (GTW)
The gross trailer weight (GTW) is the weight of the trailer
plus the weight of all cargo, consumables and equipment
(permanent or temporary) loaded in or on the trailer in its
9loaded and ready for operation9condition. The recom-
mended way to measure GTW is to put your fully loaded
trailer on a vehicle scale. The entire weight of the trailer
must be supported by the scale.
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Trailer Towing Weights (Maximum Trailer Weight Ratings)
The following chart provides the maximum trailer weight ratings towable for your given drivetrain.
Engine/
TransmissionGCWR (Gross Combined
Wt. Rating)Frontal Area Max. GTW (Gross
Trailer Wt.)Max. Tongue Wt.
(See Note 1)
6.1L Automatic 8,800 lbs (3 992 kg) 40 Sq. Ft. (3.72
square meters)3,500 lbs (1 587 kg) 350 lbs (159 kg)
Refer to local laws for maximum trailer towing speeds.
Note 1 ± The trailer tongue weight must be considered as
part of the combined weight of occupants and cargo, and
should never exceed the weight referenced on the Tire
and Loading Information placard. Refer to the ªTire±
Safety Informationº section in this manual.
Trailer and Tongue Weight
Always load a trailer with 60% to 65% of the weight in
the front of the trailer. This places 10% to 15% of the
Gross Trailer Weight (GTW) on the tow hitch of your
vehicle. Loads balanced over the wheels or heavier in the
rear can cause the trailer to swayseverelyside to side
which will cause loss of control of vehicle and trailer.
Failure to load trailers heavier in front is the cause of
many trailer accidents.
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CAUTION!
²Avoid towing a trailer for the first 500 miles (805
km) of vehicle operation. Doing so may damage
your vehicle.
²During 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.
²When hauling cargo or towing a trailer, do not over-
load your vehicle or trailer. Overloading can cause a
loss of control, poor performance or damage to brakes,
axle, engine, transmission, steering, suspension, chas-
sis structure or tires.
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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 Tips
Before setting out on a trip, practice turning, stopping
and backing the trailer in an area away from heavy
traffic.
Towing Tips Ð Automatic Transmission
The ªDº range can be selected when towing. However, if
frequent shifting occurs while in this range, the ª3º range
should be selected.
NOTE:Using the ª3º range while operating the vehicle
under heavy operating conditions will improve perfor-
mance and extend transmission life by reducing exces-
sive shifting 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. See Schedule ªBº in
section 8 of this manual for transmission fluid change
intervals.
NOTE:Check the automatic transmission fluid level
before towing.
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