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CAUTION!(Continued)
•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 perfor-
mance problems resulting from the use of such
fuels or additives is not the responsibility of the
manufacturer.
NOTE: Intentional tampering with the emissions control
system 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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WARNING!(Continued)
3. GAWR
4. Tongue weight rating for the trailer hitch utilized.
Towing Requirements — Tires
•Do not attempt to tow a trailer while using a compact
spare tire.
• Proper tire inflation pressures are essential to the safe
and satisfactory operation of your vehicle. Refer to
“Tires – General Information” in “Starting and Oper-
ating” for proper tire inflation procedures.
• Check the trailer tires for proper tire inflation pres-
sures before trailer usage.
• Check for signs of tire wear or visible tire damage
before towing a trailer. Refer to “Tires – General
Information” in “Starting and Operating” for the
proper inspection procedure. •
When replacing tires, refer to “Tires – General Infor-
mation” in “Starting and Operating” for proper tire
replacement procedures. Replacing tires with a higher
load carrying capacity will not increase the vehicle’s
GVWR and GAWR limits.Towing Requirements — Trailer Brakes
WARNING!
•Do not connect trailer brakes to your vehicle’s hy-
draulic brake lines. It can overload your brake system
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.
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CAUTION!
If the trailer weighs more than 1,000 lbs (454 kg)
loaded, it should have its own brakes and they
should be of adequate capacity. Failure to do this
could lead to accelerated brake lining wear, higher
brake pedal effort, and longer stopping distances.
• Do not interconnect the hydraulic brake system or
vacuum system of your vehicle with that of the trailer.
This could cause inadequate braking and possible
personal injury.
• An electronically actuated trailer brake controller is
required when towing a trailer with electronically
actuated brakes. When towing a trailer equipped with
a hydraulic surge actuated brake system, an electronic
brake controller is not required. •
Trailer brakes are recommended for trailers over
1,000 lbs (454 kg) and required for trailers in excess of
1,653 lbs (750 kg).
Integrated Trailer Brake Module — If Equipped
Your vehicle may have an Integrated Trailer Brake Mod-
ule (ITBM) for Electric and Electric Over Hydraulic
(EOH) trailer brakes.
NOTE: This module has been designed and verified with
electric trailer brakes and new electric over hydraulic
systems. Some previous EOH systems may not be com-
patible with ITBM.
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Light Electric Heavy Electric Light EOHHeavy EOH
Type of Trailer Brakes Electric Trailer
Brakes Electric Trailer
Brakes Electric over Hy-
draulic Trailer Brakes Electric over Hy-
draulic Trailer Brakes
Load *Under 10,000 lbs *Above 10,000 lbs *Under 10,000 lbs *Above 10,000 lbs
* The suggested selection depends and may change
depending on the customer preferences for braking per-
formance. Condition of the trailer brakes, driving and
road state may also affect the selection.
EVIC Display Messages
The trailer brake control interacts with the Electronic
Vehicle Information Center (EVIC). Display messages,
along with a single chime, will be displayed when a
malfunction is determined in the trailer connection,
trailer brake control, or on the trailer. Refer to “Electronic Vehicle Information Center” in “Understanding Your
Instrument Panel” for further information.
CAUTION!
Connecting a trailer that is not compatible with the
ITBM system may result in reduced or complete loss
of trailer braking. There may be a increase in stop-
ping distance or trailer instability which could result
in damage to your vehicle, trailer, or other property.
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WARNING!
Connecting a trailer that is not compatible with the
ITBM system may result in reduced or complete loss
of trailer braking. There may be a increase in stop-
ping distance or trailer instability which could result
in personal injury.
NOTE:
• An aftermarket controller may be available for use
with trailers with air or electric-over-hydraulic trailer
brake systems. To determine the type of brakes on
your trailer and the availability of controllers, check
with your trailer manufacturer or dealer.
• Removal of the ITBM will cause errors and it may
cause damage to the electrical system and electronic
modules of the vehicle. See your authorized dealer if
an aftermarket module is to be installed.
Towing Requirements — Trailer Lights And Wiring
Whenever you pull a trailer, regardless of the trailer size,
stoplights and turn signals on the trailer are required for
motoring safety.
The Trailer Tow Package may include a four- and seven-
pin wiring harness. Use a factory approved trailer har-
ness and connector.
NOTE: Do not cut or splice wiring into the vehicles
wiring harness.
The electrical connections are all complete to the vehicle
but you must mate the harness to a trailer connector.
Refer to the following illustrations.
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Four-Pin Connector
1 — Female Pins4 — Park
2 — Male Pin 5 — Left Stop/Turn
3 — Ground 6 — Right Stop/Turn
Seven-Pin Connector
1 — Battery5 — Ground
2 — Backup Lamps 6 — Left Stop/Turn
3 — Right Stop/Turn 7 — Running Lamps
4 — Electric Brakes
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Towing Tips
Before setting out on a trip, practice turning, stopping
and backing the trailer up in an area away from heavy
traffic.
Automatic Transmission
The “DRIVE” range can be selected when towing. The
transmission controls include a drive strategy to avoid
frequent shifting when towing. However, if frequent
shifting does occur while in DRIVE, select “TOW/
HAUL” mode or select a lower gear range (using the
Electronic Range Select (ERS) switches).
NOTE:Using “TOW/HAUL” mode or selecting a lower
gear range (using the ERS switches) while operating the
vehicle under heavy loading conditions will improve
performance and extend transmission life by reducing
excessive shifting and heat build up. This action will also
provide better engine braking. When towing a loaded trailer up steep grades at low
speeds (20 mph [32 km/h] or below), holding your
vehicle in first gear (using the ERS switches) can help to
avoid transmission overheating.
If you regularly tow a trailer for more than 45 minutes of
continuous operation, then change the automatic trans-
mission fluid and filter(s) as specified for
police, taxi,
fleet, or frequent trailer towing. Refer to “Maintenance
Schedule” for the proper maintenance intervals.
NOTE: Check the automatic transmission fluid level
before towing (6-speed automatic only).
Tow/Haul Mode
To reduce potential for automatic transmission overheat-
ing, turn the “TOW/HAUL” feature ON when driving in
hilly areas, or select a lower gear range (using the
Electronic Range Select (ERS) switches) on more severe
grades.
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Electronic Speed Control — If Equipped
•Do not use in hilly terrain or with heavy loads.
• When 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.
• Use speed control in flat terrain and with light loads to
maximize fuel efficiency.
Cooling System
To reduce potential for engine and transmission over-
heating, take the following actions:
City Driving
When stopped for short periods of time, shift the trans-
mission into NEUTRAL and increase engine idle speed.
Highway Driving
Reduce speed. Air Conditioning
Turn off temporarily.
Air Suspension System
To aid in attaching/detaching the trailer from the vehicle,
the air suspension system can be used. Refer to “Air
Suspension System” in “Starting and Operating” for
further information.
NOTE:
The vehicle must remain in the engine running
position while attaching a trailer for proper leveling of
the air suspension system.
SNOWPLOW
1500 Models Only
NOTE: Do not use this model vehicle for snowplow
applications.
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