WARNING!
If the gross trailer weight is 5,000 lbs (2,267 kg) or more,
it is recommended to use a weight-distributing hitch to
ensure stable handling of your vehicle. If you use a
standard weight-carrying hitch, you could lose control
of your vehicle and cause a collision.
Gross Combination Weight Rating (GCWR)
The GCWR is the total allowable weight of your vehicle
and trailer when weighed in combination.
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum capacity of the front and rear
axles. Distribute the load over the front and rear axles evenly.
Make sure that you do not exceed either front or rear GAWR.
Refer to “Vehicle Loading/Vehicle Certification Label” in
“Starting And Operating” for further information.
WARNING!
It is important that you do not exceed the maximum
front or rear GAWR. A dangerous driving condition
can result if either rating is exceeded. You could lose
control of the vehicle and have a collision.
Tongue Weight (TW)
The tongue weight is the downward force exerted on the
hitch ball by the trailer. You must consider this as part of
the load on your vehicle.
Trailer Frontal Area
The frontal area is the maximum height multiplied by the
maximum width of the front of a trailer.
Trailer Sway Control
The trailer sway control can be a mechanical telescoping
link that can be installed between the hitch receiver and the
trailer tongue that typically provides adjustable friction
associated with the telescoping motion to dampen any
unwanted trailer swaying motions while traveling.
If equipped, the electronic Trailer Sway Control (TSC)
recognizes a swaying trailer and automatically applies
individual wheel brakes and/or reduces engine power to
attempt to eliminate the trailer sway.
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Recommended Distribution Hitch Adjustment
Towing With 1500 Air Suspension
1. Set air suspension to normal ride height. No action isrequired if already in normal ride height.
NOTE: The vehicle must remain in the engine run position
with all doors closed while attaching a trailer for proper
leveling of the air suspension system.
2. Position the truck to be ready to connect to the trailer (do not connect the trailer).
With Weight-Distributing Hitch (Correct)Improper Adjustment Of Weight-Distributing Hitch
(Incorrect)
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Towing With 2500/3500 Air Suspension
1. Position the truck to be ready to connect to the trailer(do not connect the trailer).
NOTE: Normal Ride Height (NRH) or Alternate Trailer
Height (ATH) can be used. The vehicle must remain in the
engine running position while attaching a trailer for proper
leveling of the air suspension system. It may not be
possible to enter Alternate Trailer Height (ATH) while
lightly loaded.
2. Measure the height of the top of the front wheel opening on the fender to ground, this is height H1.
3. Attach the trailer to the vehicle without the weight distribution bars connected.
4. Measure the height of the top of the front wheel opening on the fender to ground, this is height H2.
5. Install and adjust the tension in the weight distributing bars per the manufacturers’ recommendations so that
the height of the front fender is approximately (H2-H1)/
2+H1 (about 1/2 the difference between H2 and H1
above normal ride height [H1]). 6. Preform a visual inspection of the trailer and weight
distributing hitch to confirm manufacturers’ recommen-
dations have been met.
Measurement Example Example 2500/3500
Height (mm)
H1 1030
H2 1058
H2-H1 28
(H2-H1)/2 14
(H2-H1)/2 + H1 1044
NOTE: For all towing conditions, we recommend towing
with tow haul mode engaged.
Towing With All Other 1500/2500/3500 (Non-Air Suspen-
sion)
1. Position the truck to be ready to connect to the trailer (do not connect the trailer).
2. Measure the height of the top of the front wheel opening on the fender to ground, this is height H1.
3. Attach the trailer to the vehicle without the weight distribution bars connected.
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STARTING AND OPERATING 295
Consider the following items when computing the weight
on the rear axle of the vehicle:
•The tongue weight of the trailer.
• The weight of any other type of cargo or equipment put
in or on your vehicle.
• The weight of the driver and all passengers.
NOTE: Remember that everything put into or on the
trailer adds to the load on your vehicle. Also, additional
factory-installed options or dealer-installed options must
be considered as part of the total load on your vehicle.
Refer to the “Tire And Loading Information” placard for
the maximum combined weight of occupants and cargo for
your vehicle.
Towing Requirements
To promote proper break-in of your new vehicle drivetrain
components, the following guidelines are recommended.
CAUTION!
• Do not tow a trailer at all during the first 500 miles
(805 km) the new vehicle is driven. The engine, axle
or other parts could be damaged.
(Continued)
CAUTION! (Continued)
•Then, during the first 500 miles (805 km) that a trailer
is towed, do not drive over 50 mph (80 km/h) and do
not make starts at full throttle. This helps the engine
and other parts of the vehicle wear in at the heavier
loads.
Perform the maintenance listed in the “Scheduled Servic-
ing”. Refer to “Scheduled Servicing” in “Servicing And
Maintenance” for the proper maintenance intervals. When
towing a trailer, never exceed the GAWR or GCWR ratings.
WARNING!
Improper towing can lead to a collision. 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 a collision.
(Continued)
298 STARTING AND OPERATING
WARNING!(Continued)
•When hauling cargo or towing a trailer, do not
overload your vehicle or trailer. Overloading can
cause a loss of control, poor performance or damage
to brakes, axle, engine, transmission, steering, sus-
pension, chassis structure or tires.
• Safety chains must always be used between your
vehicle and trailer. Always connect the chains to the
hook retainers of the vehicle hitch. Cross the chains
under the trailer tongue and allow enough slack for
turning corners.
• Vehicles with trailers should not be parked on a
grade. When parking, apply the parking brake on the
tow vehicle. Put the tow vehicle transmission in
PARK. For four-wheel drive vehicles, make sure the
transfer case is not in NEUTRAL. Always, block or
chock the trailer wheels.
• GCWR must not be exceeded.
• Total weight must be distributed between the tow
vehicle and the trailer such that the following four
ratings are not exceeded:
1. GVWR
(Continued)
WARNING! (Continued)
2. GTW
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” in “Servicing And Maintenance” for proper tire
inflation procedures.
• Check the trailer tires for proper tire inflation pressures
before trailer usage.
• Check for signs of tire wear or visible tire damage before
towing a trailer. Refer to “Tires” in “Servicing And
Maintenance” for the proper inspection procedure.
• When replacing tires, refer to “Tires” in “Servicing And
Maintenance” for the proper tire replacement proce-
dures. Replacing tires with a higher load carrying capac-
ity will not increase the vehicle’s GVWR and GAWR
limits.
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STARTING AND OPERATING 299
Towing Tips
Before setting out on a trip, practice turning, stopping, and
backing up the trailer in an area located 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 shift-
ing does occur while in DRIVE, select TOW/HAUL mode
or select a lower gear range (using the Electronic Range
Select (ERS) shift control).
NOTE:Using TOW/HAUL mode or selecting a lower
gear range (using the ERS shift control) while operating the
vehicle under heavy loading conditions will improve per-
formance and extend transmission life by reducing exces-
sive 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 shift control) can help to avoid
transmission overheating.
If you regularly tow a trailer for more than 45 minutes of
continuous operation, then change the automatic transmis-
sion fluid and filter(s) as specified for police, taxi, fleet, or
frequent trailer towing. Refer to the “Maintenance Plan”
for the proper maintenance intervals.
Seven-Pin Connector
1 — Battery 5 — Ground
2 — Backup Lamps 6 — Left Stop/Turn
3 — Right Stop/Turn 7 — Running Lamps
4 — Electric Brakes
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STARTING AND OPERATING 305
NOTE:Check the automatic transmission fluid level be-
fore towing.
Tow/Haul Mode
To reduce potential for automatic transmission overheat-
ing, activate TOW/HAUL mode when driving in hilly
areas, or select a lower gear range (using the Electronic
Range Select (ERS) shift control) on more severe grades.
Speed Control — If Equipped
• Do not use on 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 overheat-
ing, take the following actions:
City Driving
In city traffic — while stopped, place the transmission in
NEUTRAL, but do not 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 fur-
ther information.
NOTE:
The vehicle must remain in the engine running
position while attaching a trailer for proper leveling of the
air suspension system.
SNOWPLOW
2500/3500 Models Only
Snowplow Prep Packages are available as a factory in-
stalled option. These packages include components neces-
sary to equip your vehicle with a snowplow.
306 STARTING AND OPERATING
Vehicle front end wheel alignment was set to specifications
at the factory without consideration for the weight of the
plow. Front end toe-in should be checked and reset if
necessary at the beginning and end of the snowplow
season. This will help prevent uneven tire wear.
The blade should be lowered whenever the vehicle is
parked.
Maintain and operate your vehicle and snowplow equip-
ment following the recommendations provided by the
specific snowplow manufacturer.
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 shouldbe familiar with the area and surface to be cleaned. Reduce
speed and use extreme caution when plowing unfamiliar
areas or under poor visibility.
General Maintenance
Snowplows should be maintained in accordance with the
plow manufacturer’s instructions.
Keep all snowplow electrical connections and battery ter-
minals clean and free of corrosion.
When plowing snow, to avoid transmission and drivetrain
damage, the following precautions should be observed.
•
Operate with transfer case in 4LO when plowing small
or congested areas where speeds are not likely to exceed
15 mph (24 km/h). At higher speeds operate in 4HI.
• Vehicles with automatic transmissions should use 4LO
range when plowing deep or heavy snow for extended
periods of time to avoid transmission overheating.
• Do not shift the transmission unless the engine has
returned to idle and wheels have stopped. Make a
practice of stepping on the brake pedal while shifting the
transmission.
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