2011 GMC SIERRA service

Black plate (30,1)GMC Sierra Owner Manual - 2011
10-30 Vehicle Care
Adding Washer Fluid
The vehicle has a low washer fluid
message on the DIC that comes
on when the washer fluid is low.
The message is displayed for
15 seconds at the start of each
ignition cycle. When the WASHER
FLUID LOW ADD FLUID message
displays, washer fluid will need to
be added to the windshield washer
fluid reservoir.
Open the cap with the washer
symbol on it. Add washer fluid
until the tank is full. SeeEngine
Compartment Overview on
page 10‑6 for reservoir location. Notice:
.When using concentrated
washer fluid, follow the
manufacturer's instructions
for adding water.
.Do not mix water with
ready-to-use washer fluid.
Water can cause the solution
to freeze and damage the
washer fluid tank and other
parts of the washer system.
Also, water does not clean
as well as washer fluid.
.Fill the washer fluid tank
only three-quarters full
when it is very cold. This
allows for fluid expansion
if freezing occurs, which
could damage the tank if
it is completely full.
.Do not use engine coolant
(antifreeze) in the windshield
washer. It can damage the
windshield washer system
and paint.
Brakes
This vehicle has front disc brakes
and could have rear drum brakes or
rear disc brakes.
Disc brake pads have built-in wear
indicators that make a high-pitched
warning sound when the brake pads
are worn and new pads are needed.
The sound can come and go or
be heard all the time the vehicle is
moving, except when applying the
brake pedal firmly.
{WARNING
The brake wear warning sound
means that soon the brakes will
not work well. That could lead to
a crash. When the brake wear
warning sound is heard, have the
vehicle serviced.
Notice: Continuing to drive with
worn-out brake pads could result
in costly brake repair.

Black plate (31,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-31
Some driving conditions or climates
can cause a brake squeal when
the brakes are first applied or
lightly applied. This does not mean
something is wrong with the brakes.
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 inCapacities and
Specifications on page 12‑2.
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 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 time the brakes are applied,
with or without the vehicle moving,
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, be sure to get
new, approved replacement parts.
If this is not done, the brakes might
not work properly. For example,
installing disc brake pads that
are wrong for the vehicle, can
change the balance between the
front and rear brakes
—for the
worse. The braking performance
expected can change in many
other ways if the wrong replacement
brake parts are installed.

Black plate (39,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-39
Among those acts presumed to
constitute tampering are the acts
listed below.
Insulation:
Removal of the noise shields or any
underhood insulation.
Engine:
Removal or rendering engine speed
governor, if the vehicle has one,
inoperative so as to allow engine
speed to exceed manufacturer
specifications.
Fan and Drive:
.Removal of fan clutch, if the
vehicle has one, or rendering
clutch inoperative.
.Removal of the fan shroud, if the
vehicle has one.
Air Intake:
.Removal of the air cleaner
silencer.
.Modification of the air cleaner. Exhaust:
.Removal of the muffler and/or
resonator.
.Removal of the exhaust pipes
and exhaust pipe clamps.
Starter Switch Check
{WARNING
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. 2. Firmly apply both the parking
brake and the regular brake.
See Parking Brake on
page 9‑69.
Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts.
3. Try to start the engine in each gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer for
service.

Black plate (40,1)GMC Sierra Owner Manual - 2011
10-40 Vehicle Care
Automatic Transmission
Shift Lock Control
Function Check
{WARNING
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should
be parked on a level surface.
2. Firmly apply the parking brake. See Parking Brake on
page 9‑69.
Be ready to apply the regular
brake immediately if the vehicle
begins to move. 3. With the engine off, turn the
ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with
normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.
Ignition Transmission
Lock Check
While parked, and with the parking
brake set, try to turn the ignition
to LOCK/OFF in each shift lever
position.
.The ignition should turn to
LOCK/OFF only when the
shift lever is in P (Park).
.The ignition key should come
out only in LOCK/OFF.
Contact your dealer if service is
required.
Park Brake and P (Park)
Mechanism Check
{WARNING
When you are doing this check,
the vehicle could begin to move.
You or others could be injured
and property could be damaged.
Make sure there is room in front
of the vehicle in case it begins to
roll. Be ready to apply the regular
brake at once should the vehicle
begin to move.

Black plate (41,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-41
Park on a fairly steep hill, with the
vehicle facing downhill. Keeping
your foot on the regular brake, set
the parking brake.
.To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot
pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.
.To check the P (Park)
mechanism's holding ability:
With the engine running, shift
to P (Park). Then release the
parking brake followed by the
regular brake.
Contact your dealer if service is
required.
Wiper Blade Replacement
Windshield wiper blades should
be inspected for wear or cracking.
See Scheduled Maintenance on
page 11‑2 for more information
on wiper blade inspection.
Replacement blades come in
different types and are removed
in different ways. To remove the
wiper blade:
1. Pull the windshield wiper arm connector away from the
windshield.
2. Squeeze the grooved areas on
each side of the blade, and turn
the blade assembly away from
the arm connector.
3. Install the new blade onto thearm connector and make sure
the grooved areas are fully set
in the locked position.
For the proper type and size, see
Maintenance Replacement Parts on
page 11‑11.
Glass Replacement
If the windshield or front side
glass must be replaced, see your
dealer to determine the correct
replacement glass.

Black plate (42,1)GMC Sierra Owner Manual - 2011
10-42 Vehicle Care
Headlamp Aiming
The vehicle has a visual optical
headlamp aiming system. The aim
of the headlamps has been preset
at the factory and should need no
further adjustment.
However, if the vehicle is damaged
in a crash, the aim of the headlamps
may be affected and adjustment
may be necessary.
If oncoming vehicles flash their high
beams at you, this may mean the
vertical aim of the headlamps needs
to be adjusted.
It is recommended that the vehicle
be taken to the dealer for service if
the headlamps need to be adjusted.
It is possible, however, to re-aim the
headlamps as described.The vehicle should:.Be placed so the headlamps
are 7.6 m (25 ft) from a
light‐colored wall.
.Have all four tires on a level
surface which is level all the
way to the wall.
.Be placed so it is perpendicular
to the wall.
.Not have any snow, ice, or mud
on it.
.Be fully assembled and all other
work stopped while headlamp
aiming is being performed.
.Be loaded with a full tank of
fuel and one person or 75 kg
(160 lbs) sitting on the
driver seat.
.Have the tires properly inflated.
.Have the spare tire in its proper
location in the vehicle.Headlamp aiming is done with the
vehicle's low-beam headlamps.
The high-beam headlamps will be
correctly aimed if the low-beam
headlamps are aimed properly.
To adjust the vertical aim:
1. Open the hood. See
Hood on
page 10‑5.2. Locate the aim dot on the lens of the low‐beam headlamp.
3. Record the distance from the ground to the aim dot on the
low‐beam headlamp.

Black plate (57,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-57
Wheels and Tires
Tires
Your new vehicle comes with
high-quality tires made by
a leading tire manufacturer.
If you ever have questions about
your tire warranty and where to
obtain service, see your vehicle
Warranty booklet for details.
For additional information refer
to the tire manufacturer.
{WARNING
.Poorly maintained and
improperly used tires are
dangerous.
.Overloading the tires can
cause overheating as a result
of too much flexing. There
could be a blowout and a
serious crash. SeeVehicle
Load Limits on page 9‑25.
(Continued)
WARNING (Continued)
.Underinflated tires pose the
same danger as overloaded
tires. The resulting crash
could cause serious injury.
Check all tires frequently to
maintain the recommended
pressure. Tire pressure
should be checked when
the tires are cold.
.Overinflated tires are more
likely to be cut, punctured,
or broken by a sudden
impact—such as when
hitting a pothole. Keep tires at
the recommended pressure.
.Worn or old tires can cause
a crash. If the tread is badly
worn, replace them.
.Replace any tires that have
been damaged by impacts
with potholes, curbs, etc.
(Continued)
WARNING (Continued)
.Improperly repaired tires
can cause a crash. Only the
dealer or an authorized tire
service center should repair,
replace, dismount, and mount
the tires.
.Do not spin the tires in
excess of 55 km/h (35 mph)
on slippery surfaces such
as snow, mud, ice, etc.
Excessive spinning may
cause the tires to explode.
See Tire Pressure for High-Speed
Operation on page 10‑67 for
inflation pressure adjustment for
high speed driving.

Black plate (58,1)GMC Sierra Owner Manual - 2011
10-58 Vehicle Care
20‐Inch Tires
If your vehicle has the optional
20‐inch P275/55R20 size tires,
they are classified as touring
tires and are designed for
on road use. The low‐profile,
wide tread design is not
recommended for“off‐road”
driving or commercial uses
such as snow plowing. See
Off-Road Driving on page 9‑7
and Adding a Snow Plow
or Similar Equipment on
page 9‑125 for additional
information.
Notice: If the vehicle has
low‐profile tires, they are more
susceptible to damage from
road hazards or curb impact
than standard profile tires. Tire and/or wheel assembly
damage can occur when
coming into contact with
road hazards like, potholes,
or sharp edged objects,
or when sliding into a curb.
The vehicle warranty does
not cover this type of damage.
Keep tires set to the correct
inflation pressure and, when
possible avoid contact with
curbs, potholes, and other
road hazards.
Tire Sidewall Labeling
Useful information about a
tire is molded into the sidewall.
The following illustrations are
examples of a typical P‐Metric
and a LT‐Metric tire sidewall.
Passenger (P‐Metric) Tire
(A) Tire Size:The tire size
code is a combination of letters
and numbers used to define a
particular tire's width, height,
aspect ratio, construction type,
and service description. See the
“Tire Size” illustration later in this
section for more detail.