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Gooseneck Hitch
A gooseneck hitch is designed to be coupled
to a special hitch leveraging a hitch ball, and
is mounted over the rear axle in the
truck bed.
Fifth-Wheel Hitch
A fifth-wheel hitch is mounted over the rear
axle in the truck bed, and leverages a
hinged plate—the same type of hitch
leveraged by semi trucks. Generally,
fifth-wheel hitches accommodate large
trailers with as many as one, two, or three
axles.
Always use the correct hitch equipment for
your vehicle. Crosswinds, large trucks going
by, and rough roads can affect the trailer
and the hitch. Proper hitch equipment for your vehicle
helps maintain control of the vehicle-trailer
combination. Many trailers can be towed
using a weight-carrying hitch which has a
coupler latched to the hitch ball, or a tow
eye latched to a pintle hook. Other trailers
may require a weight-distributing hitch that
uses spring bars to distribute the trailer
tongue weight between your vehicle and
trailer axles. Fifth-wheel and gooseneck
hitches may also be used. See
“Maximum
Trailer Tongue Weight” underTrailer Towing
0 280 for weight limits with various hitch
types.
Avoid sharp turns when using a step-bumper
hitch to prevent damage. Make wider turns
to prevent contact between your trailer and
your bumper. Consider using mechanical sway controls
with any trailer. Ask a trailering professional
about sway controls or refer to the trailer
manufacturer's recommendations and
instructions.
Weight-Distributing Hitch and
Adjustment
A weight-distributing hitch may be useful
with some trailers. Use the following
guidelines to determine if a
weight-distributing hitch should be used.
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VehicleMaximum Trailer Weight Weight Distributing Hitch Hitch Distribution
2500/3500 Up to 9 080 kg (20,000 lb) Not Required* 25%
*Weight distributing hitch required on vehicles equipped with On/Off Road (OOR) and Mud Terrain (MT) tires with trailers over 10,000 lbs.
1. Front of Vehicle
2. H1/H2 Body to Ground Distance
Towing with Model 2500/3500 Trucks 1. Position the truck so that the trailer is ready to connect. Keep the trailer
detached.
2. Measure the height of the top of the front wheel opening at the fender to the
ground (H1).
3. Attach the vehicle to the trailer. Do not attach weight distribution bars at
this time.
4. Measure the height of the top of the front wheel opening on the fender to
the ground (H2). 5. Install and adjust the tension in the
weight-distributing bars per the
manufacturer’s recommendations so that
the height of the front fender is
approximately H2−[(H2−H1)/4] (1/4 the
difference between the two measured
ride heights, below the secondary ride
height {H2}).
6. Visually inspect the trailer and weight-distributing hitch to ensure that
the manufacturer’s recommendations
have been met.
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MeasurementHeight Example 2500/3500 (mm)
H1 1 040
H2 1 080
H2−H1 40
(H2−H1)/4 10
H2−[(H2−H1)/4] 1 070
Tires
.Do not tow a trailer while using a
compact spare tire on the vehicle.
.Tires must be properly inflated to support
loads while towing a trailer. SeeTires
0 345 for instructions on proper tire
inflation.
Fifth-Wheel and Gooseneck Trailering
Fifth-wheel and gooseneck trailers can be
used with many pickup models. These
trailers place a larger percentage of the
weight (kingpin weight) on the tow vehicle
than conventional trailers. Make sure this
weight does not cause the vehicle to exceed
Gross Axle Weight Rating (GAWR) or Gross
Vehicle Weight Rating (GVWR). Fifth-wheel
or gooseneck kingpin weight should be
15 –25% of the trailer weight up to the maximum amount specified on the Trailering
Information Label. See
“Trailer Weight"
under Trailer Towing 0280.
The hitch should be in the pickup bed so
that its centerline is over or near the rear
axle. Take care that it is not so far forward
that it will contact the back of the cab in
sharp turns. This is especially important for
short box pickups. Trailer pin box extensions
and sliding fifth-wheel hitch assemblies may
be used. There should be at least 15 cm
(6 in) of clearance between the top of the
pickup box and the bottom of the trailer
shelf that extends over the box.
Attach the hitch to the tow vehicle frame
rails. Do not use the pickup box for support.
Two Inch Adapter Sleeve and
Retainer Pin
The 2500/3500 series vehicles are equipped
with a 2-1/2” square receiver. An adapter is
provided to allow the use of a 2” draw bar,
along with a hitch retainer pin, and
retainer clip.
Safety Chains
Always attach safety chains between the
vehicle and the trailer. Instructions about
safety chains may be provided by the hitch
manufacturer or by the trailer manufacturer.
If the trailer being towed weighs up to
2 271 kg (5,000 lb) with a factory-installed
step bumper, safety chains may be attached
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288 Driving and Operating
to the attaching points on the bumper;
otherwise, safety chains should be attached
to holes on the trailer hitch.
Cross the safety chains under the tongue of
the trailer to help prevent the tongue from
contacting the road if it becomes separated
from the hitch. Always leave enough slack in
the safety chains to allow the combination
to turn. Never allow safety chains to drag
on the ground.
Trailer Brakes
Loaded trailers over 900 kg (2,000 lb) must
be equipped with brake systems and with
brakes for each axle. Trailer braking
equipment conforming to Canadian
Standards Association (CSA) requirement
CAN3-D313, or its equivalent, is
recommended.
State or local regulations may require
trailers to have their own braking system if
the loaded weight of the trailer exceeds
certain minimums that can vary from state
to state. Read and follow the instructions for
the trailer brakes so they are installed,
adjusted, and maintained properly. Never
attempt to tap into your vehicle's hydraulicbrake system. If you do, both the vehicle
antilock brakes and the trailer brakes may
not function, which could result in a crash.
Auxiliary Battery
If equipped, the vehicle's auxiliary battery
can be used to supply electrical power to
additional equipment that may be added,
such as a slide-in camper.
Locate the auxiliary battery connector under
the hood on the driver side of the vehicle,
next to the engine compartment fuse block.
Follow the proper installation instructions
included with any electrical equipment that
is installed.
Caution
To prevent draining the auxiliary battery,
always turn off electrical equipment
when not in use and do not use any
equipment that may exceed the
maximum amperage rating of 30 amps.
Trailer Wiring Harness
Basic Trailer Wiring
If the vehicle is not equipped with a trailer
connector on the rear bumper, a seven-wire
trailering harness is tied to the vehiclesframe. The harness requires the installation
of a trailer connector, which is available
through your dealer.
Use only a round, seven-wire connector with
flat blade terminals meeting SAE J2863
specifications for proper electrical
connectivity.
The seven-wire harness contains the
following trailer circuits:
Stop/Turn
Signal Left Yellow/Blue
Stop/Turn Signal
Right Green/Violet
Tail/Parking Lamps Gray/Brown
Reverse Lamps White/Green
Battery Feed Red/Green
Ground White
Electric Trailer Brake Blue
Heavy-Duty Trailer Wiring Harness Package
If equipped, the trailer wiring harness, with
a seven-pin connector and a four-pin
connector, is mounted on the vehicle's rear
bumper.
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Turn Signals When Towing a Trailer
When properly connected, the trailer turn
signals will illuminate to indicate the vehicle
is turning, changing lanes, or stopping.
When towing a trailer, the arrows on the
instrument cluster will illuminate even if the
trailer is not properly connected or the bulbs
are burned out.
Tow/Haul Mode
For instructions on how to enter Tow/Haul
Mode, seeDriver Mode Control 0238.
Tow/Haul assists when pulling a heavy
trailer or a large or heavy load. See Tow/
Haul Mode 0227.
Tow/Haul Mode is designed to be most
effective when the vehicle and trailer
combined weight is at least 75% of the
vehicle's Gross Combined Weight Rating
(GCWR). See “Trailer Weight” underTrailer
Towing 0280.
Tow/Haul Mode is most useful when towing
a heavy trailer or carrying a large or
heavy load:
.Through rolling terrain.
.In stop-and-go traffic.
.In busy parking lots. Operating the vehicle in Tow/Haul Mode
when lightly loaded or not towing will not
cause damage; however, it is not
recommended and may result in unpleasant
engine and transmission driving
characteristics, heavy or light steering
efforts, and reduced fuel economy.
Integrated Trailer Brake Control System
The vehicle may have an Integrated Trailer
Brake Control (ITBC) system for use with
electric trailer brakes or most electric over
hydraulic trailer brake systems. These
instructions apply to both types of electric
trailer brakes.
This symbol is on the Trailer Brake Control
Panel on vehicles with an ITBC system. The
power output to the trailer brakes is
proportional to the amount of vehicle
braking. This available power output to the
trailer brakes can be adjusted to a wide
range of trailering situations.
The ITBC system is integrated with the
vehicle’s brake, antilock brake, and
StabiliTrak/Electronic Stability Control (ESC)
systems. In trailering conditions that cause
the vehicle’s antilock brake or StabiliTrak/
ESC systems to activate, power sent to the
trailer's brakes will be automatically
adjusted to minimize trailer wheel lock-up.
This does not imply that the trailer has
StabiliTrak/ESC.
If the vehicle’s brake, antilock brake,
or StabiliTrak/ESC systems are not
functioning properly, the ITBC system may
not function fully or at all. Make sure all of
these systems are fully operational to allow
the ITBC system to function properly.
The ITBC system is powered through the
vehicle's electrical system. Turning the
ignition off will also turn off the ITBC
system. The ITBC system is fully functional
only when the ignition is in on.{Warning
Connecting a trailer that has an air brake
system may result in reduced or
complete loss of trailer braking, including
increased stopping distance or trailer
instability which could result in serious
(Continued)
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Warning (Continued)
.If the trailer brakes are not operating
properly at any time, or if a DIC
message indicates problems with the
trailer connections or trailer brakes,
carefully pull the vehicle over to the
side of the road when traffic
conditions allow.
Trailer Tires
Special Trailer (ST) tires differ from vehicle
tires. Trailer tires are designed with stiff
sidewalls to help prevent sway and to
support heavy loads. These features can
make it difficult to determine if the trailer
tire pressures are low only based on a visual
inspection.
Always check all trailer tire pressures before
each trip when the tires are cool. Low trailer
tire pressure is a leading cause of trailer tire
blow-outs.
If the vehicle is equipped with a trailer tire
pressure monitoring system, see the trailer
tire pressure monitoring system description
and the trailering app.Trailer tires deteriorate over time. The trailer
tire sidewall will show the week and year
the tire was manufactured. Many trailer tire
manufacturers recommend replacing tires
more than six years old.
Overloading is another leading cause of
trailer tire blow-outs. Never load your trailer
with more weight than the tires are
designed to support. The load rating is
located on the trailer tire sidewall.
Always know the maximum speed rating for
the trailer tires before driving. This may be
significantly lower than the vehicle tire
speed rating. The speed rating may be on
the trailer tire sidewall. If the speed rating is
not shown, the default trailer tire speed
rating is 105 km/h (65 mph).
Trailering App
Trailer Lights App
If equipped, the Trailer Lights App is on the
infotainment home screen.
Touch Start to cycle the trailer lamps on and
off to determine if they are working. The
test follows this sequence:
1. The running lights turn on first and remain on throughout the sequence. 2. The brake lights turn on for about
two seconds.
3. The left turn signal light flashes three times.
4. The right turn signal light flashes three times.
5. The reverse lights turn on for about two seconds.
6. Steps 2–5 repeat for approximately one minute and 45 seconds, or until the
test deactivates.
Touch Stop to stop the test. The test
automatically ends after one minute and
45 seconds.
The sequence also deactivates when any of
the following occur:
.The vehicle is turned off.
.The transmission is shifted out of P (Park).
.The brake pedal is pressed.
.The turn signal is activated.
.The hazard warning lights are activated.
Trailering App
If equipped, the Trailering App is on the
infotainment home screen.
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If trailer dimensions are out of range, this
feature will be unavailable.
Status View
If a trailer is connected, the Status view
shows status information for the active
trailer profile.
If no trailer is connected, the Status view
shows the last trailer profile with a status of
Not Connected.
The Status view shows:
.Lights
.Tires
.Maintenance
.Cameras
.Checklists
.Weight
.Towing AssistScroll right or left to see more options.
Each section shows high level status
information for the feature. Selecting a
section will open up a new screen with
additional information and/or options.
Selecting a camera view will open up a new
screen to preview the camera image. The
status view displays mileage and fuel
economy information.
Lights
This view displays the names of the trailer
connector pins, a graphic of the trailer
connector, and a graphic of the back of the
trailer.
Any connector pin that failed will be amber
color, and the location of the corresponding
connection will be highlighted on the
graphic of the back of the trailer.
If a trailer connection is detected without
any faults, the view will display No Issues
Found.
When a trailer is connected, the Trailering
App detects the trailer connection using the
Stop/Turn Signal lighting circuits and alerts
the driver by requesting a trailer profile
setup through the Trailering App on the
infotainment screen. If a default trailer
profile is selected, the Trailering App will not
display a Trailer Detection Alert to the user
when a trailer is connected.
When a trailer is connected and the vehicle
is off, the Trailering App will periodically
pulse the lighting circuits of the trailer to
verify it is still connected. The trailer lights
may periodically flash as a result of this
trailer connection detection. These flashes
may be more visible in dark ambient light
environments. The flashing or flickering
lights are a normal condition and the
Trailering App has built-in protections to
prevent the battery from draining. When
Theft Alert is enabled, the frequency and
pattern of this flashing will change.
If a connected trailer becomes disconnected,
a message about the trailer disconnect will
appear on the Driver Information Center
(DIC) immediately (if vehicle is on) or the
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Touch the box next to each item if that step
has been completed.
Touch
4to access a detailed view of each
step. Within each detailed view, touch Next
and Previous to navigate between steps.
Touch Clear All to clear the completed
statuses from all items in the current
checklist.
Custom Checklist Items
For each of the Trailer Profile checklists,
there is an option to create custom items to
view in the checklist. The custom item will
appear at the bottom of the checklist.
Guest Trailer and No Trailer Connected
If a Guest Trailer Profile is active, or if no
trailer is connected, the checklist will show
all of the checklists associated with Custom
Trailer Profiles in addition to default
checklist.
Weight
Touch to turn on or off the Gross Combined
Weight (GCW).
When on, an alert may be presented when
the combined weight of the vehicle and
trailer may exceed the vehicle’s Gross Combined Weight Rating (GCWR). For more
information on the GCW Alert, see
Trailer
Towing 0280.
Towing Assist
A trailer should be connected to complete
this portion of profile setup.
Touch to set up towing assist features for
the Trailer Profile. See "Towing Assist" for
details on the setup.
Guest Trailer Status View
If the Guest Trailer Profile is active, the
Status view shows:
.Lights
.Cameras
.Checklist
.Weight
Scroll right or left to see more options.
The Trailer Status view displays mileage and
fuel economy information. Mileage and fuel
economy will reset after the trailer
disconnects.
Accessory/No Trailer Status View
If the Accessory/No Trailer profile is active,
trailer status information is not available.
Trailers View
Touch the trailer profile icon/name in the
Status View to view, activate, create, edit,
or delete Trailer Profiles.
If a trailer is connected, touch the Trailer
Profile name to activate a Trailer Profile.
There can be up to five Custom Trailer
Profiles on the vehicle.
The Custom Trailer Profiles and Guest Trailer
are in order of the most frequently used.
The Accessory/No Trailer profile is shown
below the Custom Trailer Profiles and Guest
Trailer Profile.
Guest Trailer
If the Guest Trailer Profile is the active
Trailer Profile, trailer detection, lights/
connections status, theft, and the Tow/Haul
reminder alerts can be sent. The system will
not track total mileage or fuel economy, but
the system will track trip mileage and fuel
economy if the Guest Trailer Profile is active.
The TTPMS or maintenance reminders
cannot be set up for a Guest Trailer Profile.
The Guest Trailer Profile cannot be edited.