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The transmission will downshift from Overdrive to
DRIVE if the accelerator pedal is fully pressed at vehicle
speeds above approximately 35 mph (56 km/h).
When To Use “TOW/HAUL” Mode
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting oc-
curs, press the “TOW/HAUL” switch. This will improve
performance and reduce the potential for transmission
overheating or failure due to excessive shifting. When
operating in the “TOW/HAUL” mode, fifth gear is
disabled and 2-3 and 3-4 shift patterns are modified.Shifts into Overdrive (normal fourth gear) are allowed
during steady cruise (for improved fuel economy) and
automatic closed-throttle downshifts to direct gear and a
special underdrive gear (refer to “Electronic Range Se-
lect” in this section) are performed (for improved brak-
ing) when driving conditions warrant.
TOW/HAUL Switch
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The “TOW/HAUL Indicator Light” will illuminate in the
instrument cluster to indicate when the switch has been
activated. Pressing the switch a second time restores
normal operation. If the “TOW/HAUL” mode is desired,
the button must be pressed each time the engine is
started.
Torque Converter Clutch
A feature designed to improve fuel economy has been
included in the automatic transmission on your vehicle.
A clutch within the torque converter engages automati-
cally at calibrated speeds. This may result in a slightly
different feeling or response during normal operation in
the upper gears. When the vehicle speed drops or during
acceleration when the transmission downshifts to second
gear, the clutch automatically disengages.
NOTE:
•The torque converter clutch will not engage until the
transmission fluid and engine coolant (antifreeze) arewarm [usually after 1 to 3 miles (1.6 to 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. Pressing the “TOW/HAUL”
switch when the transmission is sufficiently warm will
demonstrate that the transmission is able to shift into
and out of Overdrive.
•If the vehicle has not been driven in several days, the
first few seconds of operation after shifting the trans-
mission 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
cause damage to the transmission. The torque con-
verter will refill within five seconds of shifting from
PARK into any other gear position.
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WARNING! (Continued)
•Unequal tire pressures from one side of the ve-
hicle to the other can cause the vehicle to drift to
the right or left.
•Always drive with each tire inflated to the recom-
mended cold tire inflation pressure.
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
consumption.
Ride Comfort and Vehicle Stability
Proper tire inflation contributes to a comfortable ride.
Over-inflation produces a jarring and uncomfortable
ride.
Tire Inflation Pressures
The proper cold tire inflation pressure is listed on the
driver’s side “B” Pillar.
Some vehicles may have Supplemental Tire Pressure
Information for vehicle loads that are less than the
maximum loaded vehicle condition. These pressure con-
ditions will be found in the “Supplemental Tire Pressure
Information” section of this manual.
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
check tire pressure. Do not make a visual judgement
when determining proper inflation. Radial tires may look
properly inflated even when they are under-inflated.
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To check if tires are even, lay a straight edge across all
four tires. The straight edge should touch all the tires.
CAUTION!
4500/5500 Dual Rear Tires have only one approved
direction of rotation. This is to accommodate the
asymmetrical design (tread pattern) of the On/Off
road tire.
•When replacing a flat, the spare tire may have to
be remounted on the rim or installed at a different
location to maintain the correct placement of the
tire on the wheel relative to the tire/wheel position
on the vehicle. For example, if the spare is used to
replace an outer rear tire it will have to be re-
mounted on the rim so that the wheel is dished
inward. That way the tread design of asymmetrical
tires will maintain proper position.
FUEL REQUIREMENTS
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, as it will not provide any benefit
over regular gasoline in these engines.
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 “regular” gasoline be-
fore considering service for the vehicle.
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Over 40 auto manufacturers worldwide 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. We recommend the use
of gasolines that meet the WWFC specifications 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.
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 drivability 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
manufacturer. While MTBE is an oxygenate made from
Methanol, it does not have the negative effects of
Methanol.
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E-85 Usage In Non-Flex Fuel Vehicles
Non-FFV vehicles are compatible with gasoline contain-
ing 10% ethanol (E10). Gasoline with higher ethanol
content may void the vehicle’s warranty.
If a Non-FFV vehicle is inadvertently fueled with E-85
fuel, the engine will have some or all of these symptoms:
•operate in a lean mode
•OBD II “Malfunction Indicator Light” on
•poor engine performance
•poor cold start and cold drivability
•increased risk for fuel system component corrosion
To fix a Non-FFV vehicle inadvertently fueled once with
E-85 perform the following:
•drain the fuel tank (see your authorized dealer)
•change the engine oil and oil filter
•disconnect and reconnect the battery to reset the
engine controller memory
More extensive repairs will be required for prolonged
exposure to E-85 fuel.
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 the gasoline contains MMT. It is even more
important to look for gasolines without MMT in Canada,
because MMT can be used at levels higher than those
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allowed in the United States. MMT is prohibited in
Federal and California reformulated gasoline.
Materials Added To Fuel
All gasolines sold in the United States are required to
contain effective detergent additives. Use of additional
detergents or other additives is not needed under normal
conditions and would result in unnecessary cost. There-
fore, 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 perfor-
mance, damage the emission control system.(Continued)
CAUTION! (Continued)
•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 authorized dealer for service
assistance.
•When pulling a heavy load or driving a fully-
loaded vehicle when the humidity is low and the
temperature is high, use a premium unleaded fuel
to help prevent spark knock. If spark knock per-
sists, lighten the load, or engine piston damage
may result.(Continued)
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CAUTION! (Continued)
•The use of fuel additives which are now being
sold as octane enhancers is not recommended.
Many of these products contain high concentra-
tions 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.
(Continued)
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