2006 JEEP GRAND CHEROKEE fuel

4. Wait approximately 10 seconds, then restart the en-
gine.
5. Move the shift lever to the desired gear range.
If the problem is no longer detected, the transmission will
return to normal operation. If the problem persists, P
(Park), R (Reverse), and N (Neutral) will continue to
operate. Only Second gear range will operate in the D
(Drive) shifter position. Have the transmission checked at
your authorized dealer as soon as possible.
Torque Converter Clutch
A feature designed to improve fuel economy is included
in all automatic transmissions. A clutch within the torque
converter engages automatically at a calibrated speed at
light throttle. It engages at higher speeds under heavier
acceleration. This may result in a slightly different feeling
or response during normal operation in high gear. When
the vehicle speed drops below a calibrated speed, orduring acceleration, the clutch automatically and
smoothly disengages. The feature is operational in Over-
drive and in Drive.
NOTE:The torque converter clutch will not engage
until the transmission fluid and engine coolant are warm
[usually after 1-3 miles (1.6 - 4.8 km) of driving]. Because
the engine speed is higher when the torque converter
clutch is not engaged, it may seem as if the transmission
is not shifting into Overdrive when cold. This is normal.
Manually shifting between 3 (third gear) and 4 (fourth
gear) positions (using the ERS shift control) will demon-
strate that the transmission is able to shift into and out of
Overdrive.
NOTE:If the vehicle has not been driven in several
days, the first few seconds of operation after shifting the
transmission into gear may seem sluggish. This is due to
the fluid partially draining from the torque converter into
the transmission. This condition is normal and will not
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Traction Downhill
Shift the transmission into a low gear and the transfer
case to 4WD LOW range. Let the vehicle go slowly down
the hill with all four wheels turning against engine
compression drag. This will permit you to control the
vehicle speed and direction.
When descending mountains or hills, repeated braking
can cause brake fade with loss of braking control. Avoid
repeated heavy braking by downshifting the transmis-
sion whenever possible.
After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road it is
always a good idea to check for damage. That way you
can get any problems taken care of right away and have
your vehicle ready when you need it.
•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
•Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
•Check for accumulations of plants or brush. These
things could be a fire hazard. They might hide damage
to fuel lines, brake hoses, axle pinion seals, and
propeller shafts.
•After extended operation in mud, sand, water, or
similar dirty conditions, have brake rotors, wheels,
brake linings, and axle yokes inspected and cleaned as
soon as possible.
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WARNING!
Abrasive material in any part of the brakes may
cause excessive wear or unpredictable braking. You
might not have full braking power when you need it
to prevent an accident. If you have been operating
your vehicle in dirty conditions, get your brakes
checked and cleaned as necessary.
•If you experience unusual vibration after driving in
mud, slush or similar conditions, check the wheels for
impacted material. Impacted material can cause a
wheel imbalance and freeing the wheels of it will
correct the situation.
MULTI DISPLACEMENT SYSTEM (MDS) - 5.7L
Engine Only
This feature offers improved fuel economy by shutting
off four of the engine’s eight cylinders during light load
and cruise conditions. The system is automatic with no
driver inputs or additional driving skills required.
NOTE:The MDS system may take some time to return
to full functionality after a battery disconnect.
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2. Economy—
Improper inflation pressures can cause uneven wear
patterns to develop across the tire tread. These abnormal
wear patterns will reduce tread life resulting in a need for
earlier tire replacement. Under inflation also increases
tire rolling resistance and results in higher fuel consump-
tion.
3. Ride Comfort and Vehicle Stability—
Proper tire inflation contributes to a comfortable ride.
Over inflation produces a jarring and uncomfortable ride.
Both under inflation and over inflation affect the stability
of the vehicle and can produce a feeling of sluggish
response or over responsiveness in the steering.
Unequal tire pressures can cause erratic and unpredict-
able steering response.
Unequal tire pressure from side to side may cause the
vehicle to drift left or right.Tire Inflation Pressures
The proper cold tire inflation pressure is listed on either
the face of the driver’s door, or the driver’s side“B”pillar.
The pressure should be checked and adjusted as well as
inspecting for signs of tire wear or visible damage at least
once a month. Use a good quality pocket-type gauge to
Tire Placard Location
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FUEL REQUIREMENTS
3.7/4.7L Engines (If Equipped)
All engines (except 5.7L engines) are de-
signed to meet all emissions regulations
and provide excellent fuel economy and
performance when using high quality un-
leaded“regular”gasoline having an oc-
tane rating of 87. 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 gasolines, and in some circum-
stances may result in poorer performance.
5.7L Engines (If Equipped)
The 5.7L engine is designed to meet all
emissions regulations and provide satisfac-
tory fuel economy and performance whenusing 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.
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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 gasoline contains oxygenates, and is spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.
The manufacturer strongly supports the use of reformu-
lated gasoline. Properly blended reformulated gasoline
will provide excellent performance and durability for the
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 gasoline containing METHANOL.
Gasoline containing methanol may damage critical
fuel system components.
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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
or not his/her gasoline contains MMT.
It is even more important to look for gasoline without
MMT in Canada because MMT can be used at levels
higher than allowed in the United States. MMT is pro-
hibited 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.
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.
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•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.
Carbon Monoxide Warnings
WARNING!
Carbon monoxide (CO) in exhaust gases is deadly.
Follow the precautions below to prevent carbon
monoxide poisoning:
•Do 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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