2011 GMC SIERRA tow

Black plate (114,1)GMC Sierra Owner Manual - 2011
9-114 Driving and Operating
Trailer Brakes
A loaded trailer that weighs more
than 900 kg (2,000 lbs) 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.
If the vehicle is equipped with
StabiliTrak, the trailer cannot tap
into the vehicle's hydraulic brake
system.
The trailer brake system can tap
into the vehicle's hydraulic brake
system only if:
.The trailer parts can withstand
20 650 kPa (3,000 psi) of
pressure.
.The trailer's brake system
will use less than 0.3 cc
(0.02 cubic inch) of fluid from
the vehicle's master cylinder.
Otherwise, both braking systems
will not work well or at all.If everything checks out this far,
make the brake tap at the port on
the master cylinder that sends the
fluid to the rear brakes. Use only
steel brake tubing to make the tap.
Auxiliary Battery
The auxiliary battery provision can
be used to supply electrical power
to additional equipment that may be
added, such as a slide-in camper.
If the vehicle has this provision,
this relay will be located on the
driver side of the vehicle, next to
the underhood electrical center.
Be sure to follow the proper
installation instructions included
with any electrical equipment that
is installed.
Notice:
Leaving electrical
equipment on for extended
periods will drain the battery.
Always turn off electrical
equipment when not in use
and do not use equipment that
exceeds the maximum amperage
rating for the auxiliary battery
provision.
Trailer Wiring Harness
The vehicle is equipped with one of
the following wiring harnesses for
towing a trailer or hauling a slide-in
camper.
Basic Trailer Wiring
All regular, extended cab and crew
cab pickups have a seven‐wire
trailer towing harness.
For vehicles not equipped with
heavy duty trailering, the harness
is secured to the vehicle's frame
behind the spare tire mount.
The harness requires the installation
of a trailer connector, which is
available through your dealer.
If towing a light‐duty trailer with
a standard four‐way round pin
connector, an adapter is available
from your dealer.

Black plate (115,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-115
Heavy-DutyTrailer Wiring Harness
Package
For vehicles equipped with heavy
duty trailering, the harness is
connected to a bracket on the hitch
platform. The seven-wire harness
contains the following trailer circuits:
.Yellow: Left Stop/Turn Signal
.Dark Green: Right Stop/Turn
Signal
.Brown: Taillamps
.White: Ground
.Light Green: Back-up Lamps
.Red: Battery Feed*
.Dark Blue: Trailer Brake*
*The fuses for these two circuits
are installed in the underhood
electrical center, but the wires are
not connected. They should be
connected by your dealer or a
qualified service center. The fuse
and wire for the ITBC is factory
installed and connected if the
vehicle is equipped with an ITBC.
The fuse for the battery feed is
not required if the vehicle has an
auxiliary battery. If the vehicle does
not have an auxiliary battery, have
your dealer or authorized service
center install the required fuse. If charging a remote (non-vehicle)
battery, press the Tow/Haul Mode
button, if equipped, located at
the end of the shift lever. This will
boost the vehicle system voltage
and properly charge the battery.
If the trailer is too light for Tow/
Haul Mode, or the vehicle is not
equipped with Tow/Haul, turn on
the headlamps as a second way
to boost the vehicle system and
charge the battery.

Black plate (117,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-117
If the vehicle is equipped with an
Integrated Trailer Brake Control
(ITBC) System, the blunt cuts
exist, but are not connected further
in the harness. If an aftermarket
trailer brake controller is installed,
the ITBC must be disconnected.
Do not power both ITBC and
aftermarket controllers to control
the trailer brakes at the same time.
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. SeeTow/Haul
Mode on page 9‑51 for 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” under
Trailer Towing on page 9‑95.
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.

Black plate (119,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-119
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. Trailer Brake Control PanelA. 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
(Base/Uplevel Version) on page 1‑2
or Instrument Panel (Premium
Version) on page 1‑6 for moreinformation. 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 of 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 on the vehicle’s
Driver Information Center (DIC).
See
Driver Information Center (DIC)
on page 5‑33 for more information.
The display page indicates Trailer
Gain setting, power output to
the electric trailer brakes, trailer
connection, and system operational
status.

Black plate (122,1)GMC Sierra Owner Manual - 2011
9-122 Driving and Operating
Use the following procedure to
correctly adjust Trailer Gain for
each towing condition:
1. Make sure the trailer brakes arein proper working condition.
2. Connect a properly loaded trailer to the vehicle and make
all necessary mechanical
and electrical connections.
See Vehicle Load Limits on
page 9‑25 for more information.
3. After the electrical connection is made to a trailer equipped with
electric brakes:
.A TRAILER CONNECTED
message will be briefly
displayed on the DIC.
.The Trailer Brake Display
Page will appear on the
DIC showing TRAILER
GAIN and TRAILER
OUTPUT.
.In the Trailer Output display
on the DIC, “- - - - - -”will
disappear if there is no
error present. Connecting
a trailer without electric
brakes will not clear the
six dashed lines.
4. Adjust the Trailer Gain by using the gain adjustment (+ / -)
buttons on the Trailer Brake
Control Panel.
5. Drive the vehicle with the trailer attached on a level road
surface representative of the
towing condition and free of
traffic at about 32 to 40 km/h
(20 to 25 mph) and fully apply
the Manual Trailer Brake Apply
Lever.
Adjusting trailer gain at speeds
lower than 32 to 40 km/h
(20 to 25 mph) may result
in an incorrect gain setting. 6. Adjust the Trailer Gain to just
below the point of trailer wheel
lock-up, indicated by trailer
wheel squeal or tire smoke
when a trailer wheel locks.
Trailer wheel lock-up may not
occur if towing a heavily loaded
trailer. In this case, adjust the
Trailer Gain to the highest
allowable setting for the towing
condition.
7. Re-adjust Trailer Gain any time vehicle loading, trailer loading or
road surface conditions change
or if trailer wheel lock-up is
noticed at any time while towing.

Black plate (124,1)GMC Sierra Owner Manual - 2011
9-124 Driving and Operating
SERVICE TRAILER BRAKE
SYSTEM: This message will be
displayed when there is a problem
with the ITBC system. If this
message persists over multiple
ignition cycles, there is a problem
with the ITBC system. Take the
vehicle to an authorized GM dealer
to have the ITBC system diagnosed
and repaired.
If either the CHECK TRAILER
WIRING or SERVICE TRAILER
BRAKE SYSTEM message is
displayed while driving the vehicle,
power is no longer available
to the trailer brakes. When traffic
conditions allow, carefully pull the
vehicle over to the side of the road
and turn the ignition off. Check the
wiring connection to the trailer and
turn the ignition back on. If either of
these messages continues, either
the vehicle or trailer needs service.An authorized GM dealer may
be able to diagnose and repair
problems with the trailer. However,
any diagnosis and repair of the
trailer is not covered under the
vehicle warranty. Please contact
your trailer dealer for assistance
with trailer repairs and trailer
warranty information.
Trailer Sway
Control (TSC)
Trailer Sway Control (TSC)
2500 and 3500 series vehicles with
StabiliTrak have a Trailer Sway
Control (TSC) feature. If the vehicle
is towing a trailer and the system
detects that the trailer is swaying,
the vehicle's brakes are applied
without the driver pressing the brake
pedal. If the vehicle is equipped with
the Integrated Trailer Brake Control
(ITBC) system, StabiliTrak may also
apply the trailer brakes. The TCS/
StabiliTrak warning light will flash on
the instrument panel cluster to notify
the driver to reduce speed. If the
trailer continues to sway, StabiliTrak
will reduce engine torque to help
slow the vehicle.
Adding non‐dealer accessories can
affect the vehicle's performance.
See
Accessories and Modifications
on page 10‑3 for more information.

Black plate (127,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-127
Canada
In order to calculate the amount of
weight any front accessory, such as
a snow plow, is adding to the front
axle, use the following formula:(W x (A + W.B.)) /W.B.= Weight
the accessory is adding to the
front axle.
Where: W = Weight of added accessory
A = Distance that the accessory
is in front of the front axle
W.B. = Vehicle Wheelbase For example, adding a 318 kg
(700 lb) snow plow actually adds
more than 318 kg (700 lbs) to the
front axle. Using the formula, if the
snow plow is 122 cm (4 ft) in front of
the front axle and the wheel base is
305 cm (10 ft), then:
W = 318 kg (700 lb)
A = 122 cm (4 ft)
W.B. = 305 cm (10 ft)
(W x (A + W.B.))/W.B. =
(700 x (4 + 10))/10 = 445 kg (980 lbs)
So, if the front axle reserve capacity
is more than 445 kg (980 lbs), you
could add the snow plow without
exceeding the front GAWR.
You can add heavier equipment
on the front of the vehicle if you
compensate for it by carrying fewer
passengers, less cargo, or by
positioning cargo toward the rear.

Black plate (2,1)GMC Sierra Owner Manual - 2011
10-2 Vehicle Care
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . 10-57
Tire Sidewall Labeling . . . . . . 10-58
Tire Designations . . . . . . . . . . . 10-61
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . 10-62
Tire Pressure . . . . . . . . . . . . . . . 10-66
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . 10-67
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . 10-68
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . 10-69
Tire Inspection . . . . . . . . . . . . . . 10-73
Tire Rotation . . . . . . . . . . . . . . . 10-73
Dual Tire Rotation . . . . . . . . . . 10-75
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . 10-76
Buying New Tires . . . . . . . . . . . 10-77
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . 10-79 Uniform Tire Quality
Grading . . . . . . . . . . . . . . . . . . . 10-80
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . 10-81
Wheel Replacement . . . . . . . . 10-82
Tire Chains . . . . . . . . . . . . . . . . . 10-83
If a Tire Goes Flat . . . . . . . . . . 10-84
Tire Changing . . . . . . . . . . . . . . 10-86
Full-Size Spare Tire . . . . . . . . 10-97
Jump Starting
Jump Starting . . . . . . . . . . . . . . 10-98
Towing
Towing the Vehicle . . . . . . . . 10-103
Recreational Vehicle
Towing . . . . . . . . . . . . . . . . . . . 10-103
Appearance Care
Exterior Care . . . . . . . . . . . . . . 10-108
Interior Care . . . . . . . . . . . . . . . 10-112
Floor Mats . . . . . . . . . . . . . . . . . 10-116
General Information
For service and parts needs,
visit your dealer. You will receive
genuine GM parts and GM-trained
and supported service people.
Genuine GM parts have one of
these marks: