flat tire GMC SIERRA 2011 User Guide

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.

Black plate (59,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-59
(B) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed to
GM's specific tire performance
criteria have a TPC specification
code molded onto the sidewall.
GM's TPC specifications meet
or exceed all federal safety
guidelines.
(C) DOT (Department
of Transportation)
:The
Department of Transportation
(DOT) code indicates that
the tire is in compliance
with the U.S. Department of
Transportation Motor Vehicle
Safety Standards.
(D) Tire Identification Number
(TIN)
:The letters and numbers
following DOT code are the Tire
Identification Number (TIN). The
TIN shows the manufacturer and
plant code, tire size, and date
the tire was manufactured. The TIN is molded onto both
sides of the tire, although only
one side may have the date of
manufacture.
(E) Tire Ply Material
:The type
of cord and number of plies in
the sidewall and under the tread.
(F) Uniform Tire Quality
Grading (UTQG)
:Tire
manufacturers are required
to grade tires based on three
performance factors: treadwear,
traction, and temperature
resistance. For more
information, see Uniform Tire
Quality Grading on page 10‑80.
(G) Maximum Cold Inflation
Load Limit
:Maximum load
that can be carried and the
maximum pressure needed
to support that load. For
information on recommended
tire pressure see Tire Pressure
on page 10‑66 andVehicle
Load Limits on page 9‑25.
Light Truck (LT-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.

Black plate (64,1)GMC Sierra Owner Manual - 2011
10-64 Vehicle Care
Maximum Inflation Pressure:
The maximum air pressure to
which a cold tire can be inflated.
The maximum air pressure is
molded onto the sidewall.
Maximum Load Rating
:
The load rating for a tire at the
maximum permissible inflation
pressure for that tire.
Maximum Loaded Vehicle
Weight
:The sum of curb
weight, accessory weight,
vehicle capacity weight, and
production options weight.
Normal Occupant Weight
:The
number of occupants a vehicle
is designed to seat multiplied
by 68 kg (150 lbs). See Vehicle
Load Limits on page 9‑25. Occupant Distribution
:
Designated seating positions.
Outward Facing Sidewall
:
The side of an asymmetrical tire
that has a particular side that
faces outward when mounted
on a vehicle. The side of the
tire that contains a whitewall,
bears white lettering, or bears
manufacturer, brand, and/or
model name molding that is
higher or deeper than the same
moldings on the other sidewall
of the tire.
Passenger (P-Metric) Tire
:
A tire used on passenger cars
and some light duty trucks and
multipurpose vehicles.
Recommended Inflation
Pressure
:Vehicle
manufacturer's recommended
tire inflation pressure as
shown on the tire placard.
See Tire Pressure on
page 10‑66 andVehicle
Load Limits on page 9‑25.
Radial Ply Tire
:A pneumatic
tire in which the ply cords that
extend to the beads are laid at
90 degrees to the centerline of
the tread.
Rim
:A metal support for a tire
and upon which the tire beads
are seated.
Sidewall
:The portion of a tire
between the tread and the bead.

Black plate (65,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-65
Speed Rating:An
alphanumeric code assigned to
a tire indicating the maximum
speed at which a tire can
operate.
Traction
:The friction between
the tire and the road surface.
The amount of grip provided.
Tread
:The portion of a tire
that comes into contact with
the road.
Treadwear Indicators
:Narrow
bands, sometimes called wear
bars, that show across the
tread of a tire when only 1.6 mm
(1/16 in) of tread remains.
See When It Is Time for New
Tires on page 10‑76. UTQGS (Uniform Tire
Quality Grading Standards)
:
A tire information system
that provides consumers with
ratings for a tire's traction,
temperature, and treadwear.
Ratings are determined by
tire manufacturers using
government testing procedures.
The ratings are molded into
the sidewall of the tire.
See
Uniform Tire Quality
Grading on page 10‑80.
Vehicle Capacity Weight
:
The number of designated
seating positions multiplied by
68 kg (150 lbs) plus the rated
cargo load. See Vehicle Load
Limits on page 9‑25. Vehicle Maximum Load on the
Tire
:Load on an individual tire
due to curb weight, accessory
weight, occupant weight, and
cargo weight.
Vehicle Placard
:A label
permanently attached to a
vehicle showing the vehicle
capacity weight and the
original equipment tire size
and recommended inflation
pressure. See “Tire and Loading
Information Label” underVehicle
Load Limits on page 9‑25.

Black plate (66,1)GMC Sierra Owner Manual - 2011
10-66 Vehicle Care
Tire Pressure
Tires need the correct amount
of air pressure to operate
effectively.
Notice:Neither tire
underinflation nor
overinflation is good.
Underinflated tires, or
tires that do not have
enough air, can result in:
.Tire overloading and
over-heating which
could lead to a blowout.
.Premature or
irregular wear.
.Poor handling.
.Reduced fuel economy. Overinflated tires, or tires
that have too much air, can
result in:
.Unusual wear.
.Poor handling.
.Rough ride.
.Needless damage from
road hazards.
A vehicle-specific Tire and
Loading Information label
is attached to the vehicle.
This label shows the vehicle's
original equipment tires and the
correct inflation pressures for
the tires when they are cold.
The recommended cold tire
inflation pressure, shown on
the label, is the minimum
amount of air pressure needed
to support the vehicle's
maximum load-carrying capacity. For additional information
regarding how much weight
the vehicle can carry, and an
example of the Tire and Loading
Information label, see
Vehicle
Load Limits on page 9‑25.
How you load the vehicle
affects vehicle handling and
ride comfort. Never load the
vehicle with more weight than
it was designed to carry.
When to Check
Check the tires once a month
or more.
Do not forget to check the
pressure of the spare tire, if the
vehicle has one. See Full-Size
Spare Tire on page 10‑97 for
additional information.

Black plate (67,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-67
How to Check
Use a good quality pocket-type
gauge to check tire pressure.
You cannot tell if the tires are
properly inflated simply by
looking at them. Radial tires may
look properly inflated even when
they are under-inflated. Check
the tire's inflation pressure when
the tires are cold. Cold means
the vehicle has been sitting for
at least three hours or driven no
more than 1.6 km (1 mile).
Remove the valve cap from the
tire valve stem. Press the tire
gauge firmly onto the valve to
get a pressure measurement.
If the cold tire inflation pressure
matches the recommended
pressure on the Tire and
Loading Information label,
no further adjustment is
necessary. If the pressure
is low, add air until you reach
the recommended amount.If you overfill the tire, release air
by pushing on the metal stem
in the center of the tire valve.
Recheck the tire pressure with
the tire gauge.
Be sure to put the valve caps
back on the valve stems.
They help prevent leaks by
keeping out dirt and moisture.
Tire Pressure for
High-Speed Operation
{WARNING
Driving at high speeds,
160 km/h (100 mph) or higher,
puts an additional strain on tires.
Sustained high-speed driving
causes excessive heat build up
and can cause sudden tire failure.
You could have a crash and you
or others could be killed. Some
high-speed rated tires require
(Continued)
WARNING (Continued)
inflation pressure adjustment
for high speed operation. When
speed limits and road conditions
are such that a vehicle can be
driven at high speeds, make sure
the tires are rated for high speed
operation, in excellent condition,
and set to the correct cold tire
inflation pressure for the
vehicle load.
Vehicles with P265/70R17 or
P275/55R20 size tires require
inflation pressure adjustment
when driving the vehicle at speeds
of 160 km/h (100 mph) or higher.
Set the cold tire inflation pressure
to 20 kPa (3 psi) above the
recommended cold tire pressure
shown on the Tire and Loading
Information label.

Black plate (68,1)GMC Sierra Owner Manual - 2011
10-68 Vehicle Care
When you end this high‐speed
driving, return the tires to the cold
inflation pressure shown on the
Tire and Loading Information
label. SeeVehicle Load Limits on
page 9‑25 andTire Pressure on
page 10‑66.
Tire Pressure Monitor
System
The Tire Pressure Monitor System
(TPMS) uses radio and sensor
technology to check tire pressure
levels. The TPMS sensors monitor
the air pressure in your tires and
transmit tire pressure readings to
a receiver located in the vehicle.
Each tire, including the spare
(if provided), should be checked
monthly when cold and inflated to
the inflation pressure recommended
by the vehicle manufacturer on the
vehicle placard or tire inflation pressure label. (If your vehicle has
tires of a different size than the size
indicated on the vehicle placard or
tire inflation pressure label, you
should determine the proper tire
inflation pressure for those tires.)
As an added safety feature, your
vehicle has been equipped with a
tire pressure monitoring system
(TPMS) that illuminates a low
tire pressure telltale when one or
more of your tires is significantly
under‐inflated.
Accordingly, when the low tire
pressure telltale illuminates, you
should stop and check your tires as
soon as possible, and inflate them
to the proper pressure. Driving on
a significantly under‐inflated tire
causes the tire to overheat and can
lead to tire failure. Under‐inflation
also reduces fuel efficiency and
tire tread life, and may affect the
vehicle's handling and stopping
ability.Please note that the TPMS is
not a substitute for proper tire
maintenance, and it is the driver's
responsibility to maintain correct tire
pressure, even if under‐inflation
has not reached the level to trigger
illumination of the TPMS low tire
pressure telltale.
Your vehicle has also been
equipped with a TPMS malfunction
indicator to indicate when the
system is not operating properly.
The TPMS malfunction indicator is
combined with the low tire pressure
telltale. When the system detects a
malfunction, the telltale will flash for
approximately one minute and then
remain continuously illuminated.
This sequence will continue upon
subsequent vehicle start‐ups as
long as the malfunction exists.

Black plate (69,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-69
When the malfunction indicator
is illuminated, the system may
not be able to detect or signal low
tire pressure as intended. TPMS
malfunctions may occur for a variety
of reasons, including the installation
of replacement or alternate tires or
wheels on the vehicle that prevent
the TPMS from functioning properly.
Always check the TPMS malfunction
telltale after replacing one or more
tires or wheels on your vehicle to
ensure that the replacement or
alternate tires and wheels allow
the TPMS to continue to function
properly.
SeeTire Pressure Monitor
Operation on page 10‑69 for
additional information.Federal Communications
Commission (FCC) and
Industry Canada
See Radio Frequency Statement on
page 13‑19 for information
regarding Part 15 of the Federal
Communications Commission
(FCC) rules and Industry Canada
Standards RSS-210/220/310.
Tire Pressure Monitor
Operation
This vehicle may have a Tire
Pressure Monitor System (TPMS).
The TPMS is designed to warn the
driver when a low tire pressure
condition exists. TPMS sensors are
mounted onto each tire and wheel
assembly, excluding the spare tire
and wheel assembly. The TPMS
sensors monitor the air pressure
in the tires and transmit the tire
pressure readings to a receiver
located in the vehicle.
When a low tire pressure condition
is detected, the TPMS illuminates
the low tire pressure warning light
located on the instrument cluster.
If the warning light comes on, stop
as soon as possible and inflate the
tires to the recommended pressure
shown on the Tire and Loading
Information label. See Vehicle
Load Limits on page 9‑25.
A message to check the pressure
in a specific tire displays in the
Driver Information Center (DIC).
The low tire pressure warning
light and the DIC warning message
come on at each ignition cycle
until the tires are inflated to the
correct inflation pressure. If the
vehicle has DIC buttons, tire
pressure levels can be viewed.