2010 GMC SIERRA wheel

4. Adjust the Trailer Gain by using the gainadjustment (+ / -) 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 20 to 25 mph (32 to
40 km/h) and fully apply the Manual Trailer Brake
Apply lever.
Adjusting trailer gain at speeds lower than
20 to 25 mph (32 to 40 km/h) 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.
5-69

WARNING: (Continued)
To maximize safety when towing a trailer:
.Have the exhaust system inspected for leaks
and make necessary repairs before starting
a trip.
.Never drive with the liftgate, trunk/hatch,
or rear-most window open.
.Fully open the air outlets on or under the
instrument panel.
.Adjust the Climate Control system to a setting
that brings in only outside air and set the fan
speed to the highest setting. See Climate
Control System in the Index.
For more information about carbon monoxide, see
Engine Exhaust on page 3‑54.
Towing a trailer requires a certain amount of
experience. The combination you are driving is longer
and not as responsive as the vehicle itself. Get
acquainted with the handling and braking of the rig
before setting out for the open road. Before starting, check all trailer hitch parts and
attachments, safety chains, electrical connectors,
lamps, tires and mirrors. If the trailer has electric
brakes, start the combination moving and then apply the
trailer brake controller by hand to be sure the
brakes work.
During the trip, check occasionally to be sure that the
load is secure and the lamps and any trailer brakes
still work.
Following Distance
Stay at least twice as far behind the vehicle ahead as
you would when driving the vehicle without a trailer.
This can help to avoid heavy braking and sudden turns.
Passing
More passing distance is needed when towing a trailer.
The combination will not accelerate as quickly and is
longer so it is necessary to go much farther beyond the
passed vehicle before returning to the lane.
Backing Up
Hold the bottom of the steering wheel with one hand.
To move the trailer to the left, move that hand to the left.
To move the trailer to the right, move your hand to the
right. Always back up slowly and, if possible, have
someone guide you.
5-71

Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. The vehicle could be damaged. Avoid
making very sharp turns while trailering.
When turning with a trailer, make wider turns than
normal. Do this so the trailer will not strike soft
shoulders, curbs, road signs, trees or other objects.
Avoid jerky or sudden maneuvers. Signal well in
advance.
If the trailer turn signal bulbs burn out, the arrows on the
instrument panel will still flash for turns. It is important to
check occasionally to be sure the trailer bulbs are still
working.
Driving On Grades
Reduce speed and shift to a lower gear beforestarting
down a long or steep downgrade. If the transmission is
not shifted down, the brakes might get hot and no
longer work well.
Vehicles can tow in D (Drive). Shift the transmission to
a lower gear if the transmission shifts too often under
heavy loads and/or hilly conditions.
The tow/haul mode may be used if the transmission
shifts too often. See Tow/Haul Mode on page 3‑34. When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a
lower temperature than at normal altitudes. If the engine
is turned off immediately after towing at high altitude on
steep uphill grades, the vehicle may show signs similar
to engine overheating. To avoid this, let the engine run
while parked, preferably on level ground, with the
automatic transmission in P (Park) for a few minutes
before turning the engine off. If the overheat warning
comes on, see
Engine Overheating on page 6‑34.
Parking on Hills
{WARNING:
Parking the vehicle on a hill with the trailer
attached can be dangerous. If something goes
wrong, the rig could start to move. People can be
injured, and both the vehicle and the trailer can be
damaged. When possible, always park the rig on
a flat surface.
If parking the rig on a hill: 1. Press the brake pedal, but do not shift into P (Park) yet. Turn the wheels into the curb if facing downhill
or into traffic if facing uphill.
5-72

2. Have someone place chocks under the trailerwheels.
3. When the wheel chocks are in place, release the regular brakes until the chocks absorb the load.
4. Reapply the brake pedal. Then apply the parking brake and shift into P (Park).
5. If the vehicle is four-wheel-drive, be sure the transfer case is in a drive gear and not in
N (Neutral).
6. Release the brake pedal.
{WARNING:
It can be dangerous to get out of the vehicle if the
shift lever is not fully in P (Park) with the parking
brake firmly set. The vehicle can roll.
If the engine has been left running, the vehicle
can move suddenly. You or others could be
injured. To be sure the vehicle will not move, even
when on fairly level ground, use the steps that
follow. (Continued)
WARNING: (Continued)
Always put the shift lever fully in P (Park) with the
parking brake firmly set.
If the transfer case on a four-wheel-drive vehicle
is in N (Neutral), the vehicle will be free to roll,
even if the shift lever is in P (Park). Be sure the
transfer case is in a drive gear—not in
N (Neutral).
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
2. Start the engine
3. Shift into a gear
4. Release the parking brake
5. Let up on the brake pedal.
6. Drive slowly until the trailer is clear of the chocks.
7. Stop and have someone pick up and store the chocks.
5-73

*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/
retailer 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/retailer 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.Camper/Fifth-Wheel Trailer Wiring Package
The seven-wire camper harness is located under the
front edge of the pickup box on the drivers side of the
vehicle, attached to the frame bracket. A connector
must be added to the wiring harness which connects to
the camper.
The harness contains the following camper/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
5-75

Section 6 Service and Appearance Care
Rear Axle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-48
Four-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-50
Front Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-52
Noise Control System . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-53
Tampering with Noise Control
System Prohibited . . . . . . . . . . . . . . . . . . . . . . . . . . 6-53
Headlamp Aiming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-54
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-57
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-57
Headlamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-57
Center High-Mounted Stoplamp (CHMSL) and Cargo Lamp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-58
Pickup Box Identification and Fender Marker Lamps . . . . . . . . . . . . . . . . . . 6-59
Taillamps, Turn Signal, Stoplamps and Back-up Lamps . . . . . . . . . . . . . . . . . . . . . . . . 6-60
License Plate Lamp . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-62
Replacement Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-62
Windshield Wiper Blade Replacement . . . . . . . . . . .6-63Tires
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-64
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . . . . . . . . . 6-65
Tire Terminology and Definitions . . . . . . . . . . . . . . . 6-70
Inflation - Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . 6-72
High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . . 6-74
Dual Tire Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-74
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . 6-75
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . 6-76
Tire Inspection and Rotation . . . . . . . . . . . . . . . . . . . 6-80
When It Is Time for New Tires . . . . . . . . . . . . . . . . . 6-82
Buying New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-83
Different Size Tires and Wheels . . . . . . . . . . . . . . . 6-85
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . 6-85
Wheel Alignment and Tire Balance . . . . . . . . . . . . 6-87
Wheel Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-87
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-89
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-89
Changing a Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-90
Removing the Spare Tire and Tools . . . . . . . . . . . . 6-92
Removing the Flat Tire and Installing the Spare Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-97
Secondary Latch System . . . . . . . . . . . . . . . . . . . . . 6-103
Storing a Flat or Spare Tire and Tools . . . . . . . . 6-106
Spare Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-109
6-2

Section 6 Service and Appearance Care
Appearance Care. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-110
Interior Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-110
Fabric/Carpet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-111
Leather . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-112
Instrument Panel, Vinyl, and Other Plastic Surfaces . . . . . . . . . . . . . . . . 6-112
Care of Safety Belts . . . . . . . . . . . . . . . . . . . . . . . . . . 6-112
Weatherstrips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-113
Washing Your Vehicle . . . . . . . . . . . . . . . . . . . . . . . . 6-113
Cleaning Exterior Lamps/Lenses . . . . . . . . . . . . . 6-113
Finish Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-114
Windshield and Wiper Blades . . . . . . . . . . . . . . . . . 6-114
Aluminum or Chrome-Plated Wheels and Trim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-115
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-116
Sheet Metal Damage . . . . . . . . . . . . . . . . . . . . . . . . . 6-116
Finish Damage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-116
Underbody Maintenance . . . . . . . . . . . . . . . . . . . . . . 6-116
Chemical Paint Spotting . . . . . . . . . . . . . . . . . . . . . . 6-116 Vehicle Identification
. . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-117
Vehicle Identification Number (VIN) . . . . . . . . . . . 6-117
Service Parts Identification Label . . . . . . . . . . . . . 6-117
Electrical System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-117
Add-On Electrical Equipment . . . . . . . . . . . . . . . . . 6-117
Windshield Wiper Fuses . . . . . . . . . . . . . . . . . . . . . . 6-118
Power Windows and Other Power Options . . . 6-118
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . . 6-118
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . 6-119
Center Instrument Panel Fuse Block . . . . . . . . . 6-121
Underhood Fuse Block . . . . . . . . . . . . . . . . . . . . . . . 6-122
Capacities and Specifications . . . . . . . . . . . . . . . . . .6-126
6-3

Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to torque specifications in
Capacities and Specifications on page 6‑126.
If the vehicle has rear drum brakes, they do not have
wear indicators, but if a rear brake rubbing noise is
heard, have the rear brake linings inspected
immediately. Rear brake drums should be removed and
inspected each time the tires are removed for rotation or
changing. Drum brakes have an inspection hole to
inspect lining wear during scheduled maintenance.
When the front brake pads are replaced, have the rear
brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
Brake Pedal Travel
See your dealer/retailer if the brake pedal does not
return to normal height, or if there is a rapid increase in
pedal travel. This could be a sign that brake service
might be required.
Brake Adjustment
Every brake stop, the brakes adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. The vehicle
was designed and tested with top-quality brake parts.
When parts of the braking system are replaced—for
example, when the brake linings wear down and new
ones are installed —be sure to get new approved
replacement parts. If this is not done, the brakes might
not work properly. For example, if someone puts in
brake linings that are wrong for the vehicle, the balance
between the front and rear brakes can change —for the
worse. The braking performance expected can change
in many other ways if the wrong replacement brake
parts are installed.
6-42