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Weight of the Trailer Tongue
The tongue load (A) of any trailer is very important
because it is also part of the vehicle weight. The Gross
Vehicle Weight (GVW) includes the curb weight of the
vehicle, any cargo carried in it, and the people who will
be riding in the vehicle as well as trailer tongue weight.
Vehicle options, equipment, passengers and cargo in
the vehicle reduce the amount of tongue weight the
vehicle can carry, which will also reduce the trailer
weight the vehicle can tow. SeeLoading the Vehicle
on
page 5‑29for more information about the vehicle's
maximum load capacity.
Trailer tongue weight (A) should be 10 percent to
15 percent and fifth wheel or gooseneck kingpin weight
should be 15 to 25 percent of the loaded trailer weight
up to the maximums for vehicle series and hitch type
shown below:
Vehicle Series Hitch Type Maximum
Tongue Weight
1500 Weight Carrying 272 kg (600 lbs)
2500 Weight Carrying 453 kg (1,000 lbs)
1500 Weight Distributing 499 kg (1,100 lbs)
2500 Weight Distributing 680 kg (1,500 lbs)
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Do not exceed the maximum allowable tongue weight
for the vehicle. Choose the shortest hitch extension that
will position the hitch ball closest to the vehicle. This will
help reduce the effect of trailer tongue weight on the
rear axle.
Trailering may be limited by the vehicle's ability to carry
tongue weight. Tongue or kingpin weight cannot cause
the vehicle to exceed the GVWR (Gross Vehicle Weight
Rating) or the RGAWR (Rear Gross Axle Weight
Rating). See“Total Weight on the Vehicle's Tires” later
in this section for more information.
After loading the trailer, weigh the trailer and then the
tongue, separately, to see if the weights are proper.
If they are not, adjustments might be made by moving
some items around in the trailer.
Total Weight on the Vehicle's Tires
Be sure the vehicle's tires are inflated to the inflation
pressures found on the Certification label on the drivers
door or see Loading the Vehicle
on page 5‑29for more
information. Make sure not to exceed the GVWR limit
for the vehicle, or the RGAWR, with the tow vehicle and
trailer fully loaded for the trip including the weight of the
trailer tongue. If using a weight distributing hitch, make
sure not to exceed the RGAWR before applying the
weight distribution spring bars.
Weight of the Trailering Combination
It is important that the combination of the tow
vehicle and trailer does not exceed any of its weight
ratings —GCWR, GVWR, RGAWR, Trailer Weight
Rating or Tongue Weight. The only way to be sure it is
not exceeding any of these ratings is to weigh the tow
vehicle and trailer combination, fully loaded for the trip,
getting individual weights for each of these items.
Hitches
The correct hitch equipment helps maintain combination
control. Most small-to-medium trailers can be towed
with a weight carrying hitch which simply features a
coupler latched to the hitch ball. Larger trailers may
require a weight distributing hitch that uses spring
bars to distribute the trailer tongue weight among the
two vehicle and trailer axles. See “Weight of the Trailer
Tongue” earlier in this section for rating limits with
various hitch types.
If a step-bumper hitch will be used, the bumper could
be damaged in sharp turns. Make sure there is ample
room when turning to avoid contact between the trailer
and the bumper.
Consider using sway controls with any trailer. Ask a
trailering professional about sway controls or refer
to the trailer manufacturer's recommendations and
instructions.
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Weight‐Distributing Hitch Adjustment
A:Body to Ground Distance
B: Front of Vehicle
When using a weight-distributing hitch, the spring bars
should be adjusted so the distance (A) is the same after
coupling the trailer to the tow vehicle and adjusting the
hitch.
Safety Chains
Always attach chains between the vehicle and the
trailer. 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. Instructions
about safety chains may be provided by the hitch
manufacturer or by the trailer manufacturer. If the trailer
being towed weighs up to 5,000 lbs (2 271 kg) with a
factory-installed step bumper, safety chains may be
attached to the attaching points on the bumper,
otherwise, safety chains should be attached to holes
on the trailer hitch platform. Always leave just enough
slack so the combination can turn. Never allow safety
chains to drag on the ground.
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Tow/Haul Mode
Pressing this button
at the end of the shift
lever turns on and off
the tow/haul mode.
This indicator light on
the instrument panel
cluster comes on when
the tow/haul mode is on.Tow/Haul is a feature that assists when pulling a heavy
trailer or a large or heavy load. See
Tow/Haul Mode
on
page 3‑38for more information.
Tow/Haul is designed to be most effective when
the vehicle and trailer combined weight is at least
75 percent of the vehicle's Gross Combined Weight
Rating (GCWR). See “Weight of the Trailer” earlier in
the section. Tow/Haul is most useful under the following
driving conditions:
.When pulling a heavy trailer or a large or heavy
load through rolling terrain.
.When pulling a heavy trailer or a large or heavy
load in stop and go traffic.
.When pulling a heavy trailer or a large or heavy
load in busy parking lots where improved low
speed control of the vehicle is desired.
Operating the vehicle in Tow/Haul when lightly loaded
or with no trailer at all will not cause damage. However,
there is no benefit to the selection of Tow/Haul when the
vehicle is unloaded. Such a selection when unloaded
may result in unpleasant engine and transmission
driving characteristics and reduced fuel economy.
Tow/Haul is recommended only when pulling a heavy
trailer or a large or heavy load.
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Trailer Brakes
A loaded trailer that weighs more than 2,000 lbs
(900 kg) needs to have its own brake system that is
adequate for the weight of the trailer. Be sure to read
and follow the instructions for the trailer brakes so they
are installed, adjusted and maintained properly.
Since the vehicle is equipped with StabiliTrak
®, the
trailer brakes cannot tap into the vehicle's hydraulic
system.
Integrated Trailer Brake Control System
The vehicle may have an
Integrated Trailer Brake
Control (ITBC) system for
electric trailer brakes. This symbol is located on the Trailer Brake Control
Panel on vehicles with an Integrated Trailer Brake
Control System. The power output to the trailer brakes
is based on the amount of brake pressure being applied
by the vehicle’
s brake system. 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,
anti‐lock brake and StabiliTrak systems. In trailering
conditions that cause the vehicle’s anti‐lock brake or
StabiliTrak 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 the StabiliTrak system.
If the vehicle’s brake, anti‐lock brake or StabiliTrak
systems are not functioning properly, the ITBC system
may not be fully functional or may not function at all.
Make sure all of these systems are fully operational to
ensure full functionality of the ITBC system.
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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 or in RUN.
The ITBC system can only be used with trailers with
electric brakes.
{WARNING:
Connecting a trailer that is not compatible with the
ITBC system may result in reduced or complete
loss of trailer braking. There may be an increase
in stopping distance or trailer instability which
could result in personal injury or damage to the
vehicle, trailer, or other property. An aftermarket
controller may be available for use with trailers
with surge, air or electric‐over‐hydraulic trailer
brake systems. To determine the type of brakes
on the trailer and the availability of controllers,
check with your trailer manufacturer or dealer.When trailering, make sure of the following:
.The ITBC system is used only with trailers that are
equipped with electric brakes.
.All applicable local and federal laws and
regulations are followed.
.All electrical and mechanical connections to the
trailer are made correctly.
.The trailer
’s brakes are in proper working
condition.
.The trailer and vehicle are properly loaded for the
towing condition.
The ITBC system is a factory installed item.
Out‐of‐factory installation of this system should not
be attempted. GM is not responsible for warranty or
performance of the system resulting from out‐of‐factory
installation.
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Trailer Brake Control Panel
A. Manual Trailer Brake Apply Lever
B. Trailer Gain Adjustment Buttons
The ITBC system has a control panel located on the
instrument panel to the left of the steering column. See
Instrument Panel
on page 1‑2. The control panel
allows adjustment to the amount of output, referred to
as trailer gain, available to the electric trailer brakes and
allows manual application the trailer brakes. The Trailer
Brake Control Panel is used along with the Trailer Brake
Display Page on the DIC to adjust and display power
output to the trailer brakes.
Trailer Brake DIC Display Page
The ITBC system displays messages into the vehicle’s
Driver Information Center (DIC). See DIC Warnings and
Messages
on page 4‑61for more information.
The display page indicates Trailer Gain setting, power
output to the electric trailer brakes, trailer connection
and system operational status.
The Trailer Brake Display Page can be displayed by
performing any of the following actions:
.Scrolling through the DIC menu pages using the
odometer trip stem or the DIC Vehicle Information
button (if equipped).
.Pressing a Trailer Gain button –If the Trailer Brake
Display Page is not currently displayed, pressing a
Trailer Gain button will first recall the current Trailer
Gain setting. After the Trailer Brake Display Page
is displayed, each press and release of the gain
buttons will then cause the Trailer Gain setting to
change.
.Activating the Manual Trailer Brake Apply lever
.Connecting a trailer equipped with electric trailer
brakes
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All DIC warning and service messages must first be
acknowledged by the driver by pressing the odometer
trip stem or the DIC Vehicle Information button
(if equipped) before the Trailer Brake Display Page
can be displayed and Trailer Gain can be adjusted.
TRAILER GAIN–This setting is displayed anytime the
Trailer Brake Display Page is active. This setting can be
adjusted from 0.0 to 10.0 with either a trailer connected
or disconnected. To adjust the Trailer Gain, press one
of the Trailer Gain adjustment buttons located on the
Trailer Brake Control Panel. Press and hold a gain
button to cause the Trailer Gain to continuously adjust.
To turn the output to the trailer off, adjust the Trailer
Gain setting to 0.0 (zero).
0.0 (zero) gain is the factory default setting. To properly
adjust trailer gain, see the Trailer Gain Adjustment
Procedure later in this section. TRAILER OUTPUT
–This is displayed any time a trailer
with electric brakes is connected. Output to the electric
brakes is based on the amount of vehicle braking
present and relative to the Trailer Gain setting. Output is
displayed from 0 to 10 bars for each gain setting.
The Trailer Output will indicate “- - - - - -“on the Trailer
Brake Display Page whenever the following occur:
.No trailer is connected.
.A trailer without electric brakes is connected
(no DIC message is displayed).
.A trailer with electric brakes has become
disconnected (a CHECK TRAILER WIRING
message will also be displayed on the DIC).
.There is a fault present in the wiring to the electric
trailer brakes (a CHECK TRAILER WIRING
message will also be displayed on the DIC).
.There is a fault in the ITBC system (a SERVICE
TRAILER BRAKE SYSTEM message will also be
displayed in the DIC).
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