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Operating Tips
Fast Cooldown
For a fast cooldown, turn the blower fan rotary knob to
the extreme right position, turn the mode control to the
panel fresh position, press the snowflake button to turn
on the air conditioning, and drive with the windows
open for the first few minutes. Once the hot air has been
expelled, close the windows and press the recirculation
pushbutton on dual zone control, or switch the mode
from panel/fresh to panel/recirculate on single zone
control. When a comfortable condition has been reached,
choose a mode position and adjust the temperature
control slide and blower speed as necessary to maintain
comfort. For high humidity conditions it may be neces-
sary to remain in the Recirculation mode to maintain
comfort.
Window Fogging
Windows will fog on the inside when the humidity inside
the vehicle is high. This often occurs in mild or cool
temperatures when it’s rainy or humid. In most cases
turning on the air conditioning (pressing the snowflake
button) will clear the fog. Adjust the temperature control,
air direction and blower speed to maintain comfort.
As the temperature gets colder it may be necessary to
direct air onto the windshield by using the Mix mode
position on the control. Adjust the temperature control
and blower speed to maintain comfort. Higher blower
speeds will reduce fogging. Interior fogging on the
windshield can be quickly removed by selecting the
defrost mode.
Regular cleaning of the inside of the windows with a
non-filming cleaning solution (vinegar and water works
very well) will help prevent contaminates (cigarette
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smoke, perfumes, etc.) from sticking to the windows.
Contaminates increase the rate of window fogging.
Summer Operation
Air conditioned vehicles must be protected with a high
quality antifreeze coolant during summer to provide
proper corrosion protection and to raise the boiling point
of the coolant for protection against overheating. A 50 %
concentration is recommended. Refer to ”Engine Cool-
ant” under “ Fluids, Lubricants and Genuine Parts” in
section 7.
When using the air conditioner in extremely heavy traffic
in hot weather, especially when towing a trailer, addi-
tional engine cooling may be required. If this situation is
encountered, operate the transmission in a lower gear to
increase engine RPM, coolant flow and fan speed. When
stopped in heavy traffic, it may be necessary to shift into
NEUTRAL and depress the accelerator slightly for fast
idle operation to increase coolant flow and fan speed.Your air conditioning system is also equipped with an
automatic recirculation system. When the system senses
a heavy load or high heat conditions, it may use partial
Recirculation A/C mode to provide additional comfort.
Winter Operation
When operating the system during the winter months,
make sure the air intake, located directly in front of the
windshield, is free of ice, slush, snow, or other
obstructions.
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CAUTION!
After inspecting or adjusting the tire pressure, al-
ways reinstall the valve stem cap (if equipped). This
will prevent moisture and dirt from entering the
valve stem, which could damage the valve stem.
Inflation pressures specified on the placard are always
“cold tire inflation pressure.” Cold tire inflation pressure
is defined as the tire pressure after the vehicle has not
been driven for at least three hours, or driven less than
1 mile (1 km) after a three hour period. The cold tire
inflation pressure must not exceed the maximum infla-
tion pressure molded into the tire sidewall.
Check tire pressures more often if subject to a wide range
of outdoor temperatures, as tire pressures vary with
temperature changes. Tire pressures change by approximately 1 psi (7 kPa) per
12°F (7°C) of air temperature change. Keep this in mind
when checking tire pressure inside a garage, especially in
the winter.
Example: If garage temperature = 68°F (20°C) and the
outside temperature = 32°F (0°C) then the cold tire
inflation pressure should be increased by 3 psi (21 kPa),
which equals 1 psi (7 kPa) for every 12°F (7°C) for this
outside temperature condition.
Tire pressure may increase from 2 to 6 psi (13 to 40 kPa)
during operation. DO NOT reduce this normal pressure
build up or your tire pressure will be too low.
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FUEL REQUIREMENTS
5.7L Gas Engine
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 “regular” gasoline be-
fore considering service for the vehicle.
Over 40 auto manufacturers 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. 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.
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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, and 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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WARNING! (Continued)
•Guard against carbon monoxide with proper
maintenance. Have the exhaust system inspected
every time the vehicle is raised. Have any abnor-
mal conditions repaired promptly. Until repaired,
drive with all side windows fully open.
ADDING FUEL
The fuel tank filler tube has a restricting door about 2 in
(50 mm) inside the opening. If using a portable fuel
container, it should have a flexible nozzle long enough to
force open the restricting door.
CAUTION!
•Damage to the fuel system or emissions control
system could result from using an improper fuel
tank filler tube cap (gas cap). A poorly fitting cap
could let impurities into the fuel system. Also, a
poorly-fitted aftermarket cap can cause the MIL
(Malfunction Indicator Light) to illuminate due to
fuel vapors escaping from the system.
•A poorly fitting gas cap may cause the MIL to turn
on.
•To avoid fuel spillage and overfilling, do not “top
off” the fuel tank after filling.
NOTE: When the fuel nozzle “clicks” or shuts off the
fuel tank is full.
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NOTE:Check the automatic transmission fluid level
before towing.
Towing Tips — Tow/Haul (If Equipped)
To reduce potential for automatic transmission overheat-
ing, turn the “TOW HAUL OD/OFF” feature ON when
driving in hilly areas or shift the transmission to Drive
position 2 on more severe grades.
Towing Tips — Electronic Speed Control (If
Equipped)
\25
Do not use in hilly terrain or with heavy loads.
\25When using the speed control, if you experience speed
drops greater than 10 mph (16 km/h), disengage until
you can get back to cruising speed.
\25Use speed control in flat terrain and with light loads to
maximize fuel efficiency.
Towing Tips — Cooling System
To reduce potential for engine and transmission over-
heating, take the following actions:
\25City Driving
When stopped for short periods of time, put transmission
in NEUTRAL and increase engine idle speed.
\25Highway Driving
Reduce speed.
\25Air Conditioning
Turn off temporarily.
SNOWPLOW
Snowplow Prep Packages are available as a factory
installed option. These packages include components
necessary to equip your vehicle with a snowplow.
NOTE: Before installation of a snowplow it is highly
recommended that the owner/installer obtain and follow
the recommendations contained within the current
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Over the Road Operation With Snowplow
Attached
The blade restricts air flow to the radiator and causes the
engine to operate at higher than normal temperatures.
Therefore, when transporting the plow, angle the blade
completely and position it as low as road or surface
conditions permit. Do not exceed 40 mph (64 km/h). The
operator should always maintain a safe stopping distance
and allow adequate passing clearance.
Operating Tips
Under ideal snow plowing conditions, 20 mph (32 km/h)
should be maximum operating speed. The operator
should be familiar with the area and surface to be
cleaned. Reduce speed and use extreme caution when
plowing unfamiliar areas or under poor visibility.
NOTE:During snowplow usage on vehicles equipped
with an overhead console module, the outside tempera-
ture display will show higher temperatures than the outside ambient temperature. The higher displayed tem-
perature is due to blocked or reduced airflow to the
underhood ambient temperature sensor by the snow-
plow. This is common and outside temperature display
operation will return to normal when the snowplow is
removed.
General Maintenance
Snowplows should be maintained in accordance with the
plow manufacturer’s instructions.
Keep all snowplow electrical connections and battery
terminals clean and free of corrosion.
When plowing snow, to avoid transmission and drive-
train damage, the following precautions should be ob-
served.
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