2012 CHEVROLET SUBURBAN towing

Black plate (70,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
9-70 Driving and Operating
Maintenance When Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See
Scheduled Maintenance on
page 11‑3. Things that are
especially important in trailer
operation are automatic
transmission fluid, engine oil,
axle lubricant, belts, cooling
system and brake system. It is a
good idea to inspect these before
and during the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Trailer Towing
If the vehicle has a hybrid engine,
see the Hybrid supplement for more
information.
Do not tow a trailer during break‐in.
SeeNew Vehicle Break-In on
page 9‑21 for more information.
{WARNING
The driver can lose control when
pulling a trailer if the correct
equipment is not used or the
vehicle is not driven properly.
For example, if the trailer is too
heavy, the brakes may not work
well—or even at all. The driver
and passengers could be
seriously injured. The vehicle may
also be damaged; the resulting
repairs would not be covered by
the vehicle warranty. Pull a trailer
(Continued)
WARNING (Continued)
only if all the steps in this section
have been followed. Ask your
dealer for advice and information
about towing a trailer with the
vehicle.
Notice: Pulling a trailer
improperly can damage the
vehicle and result in costly
repairs not covered by the
vehicle warranty. To pull a trailer
correctly, follow the advice in this
section and see your dealer for
important information about
towing a trailer with the vehicle.
To identify the trailering capacity of
the vehicle, read the information in
“Weight of the Trailer” that appears
later in this section.

Black plate (75,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
Driving and Operating 9-75
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.
Towing Equipment
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” inTrailer Towing on
page 9‑70 for rating limits with
various hitch types.
Consider using 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
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.

Black plate (76,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
9-76 Driving and Operating
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 2 271 kg
(5,000 lbs) 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.
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.
Since the vehicle is equipped with
StabiliTrak
®, the trailer brakes
cannot tap into the vehicle's
hydraulic system.
Trailer Wiring Harness
The vehicle is equipped with the
following wiring harnesses for
towing a trailer.
Basic Trailer Wiring
The trailer wiring harness, with a
seven-pin connector, is located at
the rear of the vehicle and is tied to
the vehicle's frame. The harness
connector can be plugged into a
seven-pin universal heavy-duty
trailer connector available through
your dealer. 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.

Black plate (77,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
Driving and Operating 9-77
Heavy-Duty Trailer Wiring Harness
Package
The vehicle is equipped with the
seven-wire trailer towing harness.
This harness with a seven-pin
universal trailer connector is
attached 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.
If charging a remote (non-vehicle)
battery, press the tow/haul mode
button 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, turn on the
headlamps as a second way to
boost the vehicle system and
charge the battery.
Electric Brake Control Wiring
Provisions
These wiring provisions are
included with the vehicle as part of
the trailer wiring package. These
provisions are for an electric brake
controller. The instrument panel
contains blunt cut wires near the
data link connector for the trailer
brake controller. The harness
contains the following wires:
.Dark Blue: Brake Signal to
Trailer Connector
.Red/Black: Battery
.Light Blue/White: Brake Switch
.White: Ground
It should be installed by your dealer
or a qualified service center.
If the vehicle is equipped with an
ITBC, 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.

Black plate (80,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
9-80 Driving and Operating
.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 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. 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
Driver Information Center (DIC) on
page 5‑26
for 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

Black plate (82,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
9-82 Driving and Operating
Manual Trailer Brake Apply
The Manual Trailer Brake Apply
Lever is located on the Trailer
Brake Control Panel and is used to
apply the trailer’s electric brakes
independent of the vehicle’s brakes.
This lever is used in the Trailer Gain
Adjustment Procedure to properly
adjust the power output to the trailer
brakes. Sliding the lever to the left
will apply only the trailer brakes.
The power output to the trailer is
indicated in the Trailer Brake
Display Page in the DIC. If the
vehicle’s service brakes are applied
while using the Manual Trailer Brake
Apply Lever, the trailer output power
will be the greater of the two.
The trailer and the vehicle's brake
lamps will come on when either
vehicle braking or manual trailer
brakes are applied. Trailer Gain Adjustment Procedure
Trailer Gain should be set for a
specific trailering condition and
must be adjusted any time vehicle
loading, trailer loading or road
surface conditions change.
Setting the Trailer Gain properly is
needed for the best trailer stopping
performance. A trailer that is
over-gained may result in locked
trailer brakes. A trailer that is
under-gained may result in not
enough trailer braking. Both of these
conditions may result in poorer
stopping and stability of the vehicle
and trailer.
Use the following procedure to
correctly adjust Trailer Gain for each
towing condition:
1. Make sure the trailer brakes are
in 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 9‑16
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
display.
.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.

Black plate (83,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
Driving and Operating 9-83
5. Drive the vehicle with the trailerattached 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
Other ITBC Related DIC Messages
In addition to displaying TRAILER
GAIN and TRAILER OUTPUT
through the DIC, trailer connection
and ITBC system status is displayed
in the DIC.
TRAILER CONNECTED –This
message will be briefly displayed
when a trailer with electric brakes is
first connected to the vehicle. This
message will automatically turn off
in about ten seconds. The driver
can also acknowledge this message
before it automatically turns off.
CHECK TRAILER WIRING –This
message will be displayed if:
1. The ITBC system first
determines connection to a
trailer with electric brakes and
then the trailer harness becomes
disconnected from the vehicle. If the disconnect occurs while
the vehicle is stationary, this
message will automatically
turn off in about thirty seconds.
This message will also turn off if
the driver acknowledges this
message off or if the trailer
harness is re-connected.
If the disconnect occurs while
the vehicle is moving, this
message will continue until
the ignition is turned off. This
message will also turn off if
the driver acknowledges this
message off or if the trailer
harness is re-connected.
2. There is an electrical fault in the wiring to the electric trailer
brakes. This message will
continue as long as there is an
electrical fault in the trailer
wiring. This message will
also turn off if the driver
acknowledges this message off.

Black plate (84,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
9-84 Driving and Operating
To determine if the electrical fault
is on the vehicle side or trailer
side of the trailer wiring harness
connection, do the following:
1. Disconnect the trailer wiringharness from the vehicle.
2. Turn the ignition OFF.
3. Wait ten seconds, then turn the ignition back to RUN.
4. If the CHECK TRAILER WIRING message re-appears, the
electrical fault is on the
vehicle side.
If the CHECK TRAILER WIRING
message only re-appears when
connecting the trailer wiring
harness to the vehicle, the
electrical fault is on the
trailer side.
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
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)
Non-hybrid 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
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. See
StabiliTrak
®
System on page 9‑45 for more
information.
Adding non‐dealer accessories can
affect the vehicle performance. See
Accessories and Modifications on
page 10‑3 for more information.