2006 GMC SIERRA tire type

Setting Preset PTYs (RDS Only)
These buttons have factory PTY presets. Up to 12 PTYs
(six FM1 and six FM2), can be programmed on the
six numbered pushbuttons, by performing the following
steps:
1. Press BAND to select FM1 or FM2.
2. Press the TYPE button to activate program type
select mode. TYPE and the last selected PTY will
appear on the display.
3. Turn the TYPE knob or press and release the
TYPE button to select a PTY.
4. Press and hold one of the six numbered pushbuttons
until you hear a beep. Whenever that numbered
pushbutton is pressed, the PTY that was set will
return.
5. Repeat the steps for each pushbutton.
RDS Messages
INFO (Information):If the current station has a
message, the information symbol will appear on the
display. Press this button to see the message. The
message may display the artist, song title, call in
phone numbers, etc.If the entire message is not displayed, parts of the
message will appear every three seconds. To scroll
through the message, press and release the INFO button.
A new group of words will appear on the display after
every press of the button. Once the complete message
has been displayed, the information symbol will
disappear from the display until another new message is
received. The last message can be displayed by pressing
the INFO button. You can view the last message until a
new message is received or a different station is tuned to.
Radio Messages
CAL ERR (Calibration Error):The audio system has
been calibrated for your vehicle from the factory. If CAL
ERR appears on the display, it means that the radio has
not been congured properly for the vehicle and must be
returned to your GM dealer for service.
LOCKED:This message is displayed when the
THEFTLOCK
®system has locked up. Take the
vehicle to your GM dealer for service.
If any error occurs repeatedly, or if an error cannot be
corrected, contact your GM dealer.
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Check your mirrors, glance over your shoulder and
start your left lane change signal before moving out
of the right lane to pass. When you are far enough
ahead of the passed vehicle to see its front in your
inside mirror, activate your right lane change signal
and move back into the right lane. Remember that if
your passenger side outside mirror is convex, the
vehicle you just passed may seem to be farther away
from you than it really is.
Try not to pass more than one vehicle at a time on
two-lane roads. Reconsider before passing the next
vehicle.
Do not overtake a slowly moving vehicle too rapidly.
Even though the brake lamps are not ashing, it may
be slowing down or starting to turn.
If you are being passed, make it easy for the
following driver to get ahead of you. Perhaps you
can ease a little to the right.
Loss of Control
Let us review what driving experts say about what
happens when the three control systems — brakes,
steering, and acceleration — do not have enough friction
where the tires meet the road to do what the driver has
asked.
In any emergency, do not give up. Keep trying to steer
and constantly seek an escape route or area of less
danger.
Skidding
In a skid, a driver can lose control of the vehicle.
Defensive drivers avoid most skids by taking reasonable
care suited to existing conditions, and by not overdriving
those conditions. But skids are always possible.
The three types of skids correspond to your vehicle’s
three control systems. In the braking skid, your wheels
are not rolling. In the steering or cornering skid, too much
speed or steering in a curve causes tires to slip and lose
cornering force. And in the acceleration skid, too much
throttle causes the driving wheels to spin.
A cornering skid is best handled by easing your foot off
the accelerator pedal.
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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.
(A) Tire Size:The tire size code is a combination of
letters and numbers used to dene 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.(B) TPC Spec (Tire Performance Criteria
Specication):Original equipment tires designed to
GM’s specic tire performance criteria have a TPC
specication code molded onto the sidewall. GM’s
TPC specications 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 Identication Number (TIN):The letters and
numbers following DOT code are the Tire Identication
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 5-86.
(G) Maximum Cold Ination Load Limit:Maximum
load that can be carried and the maximum pressure
needed to support that load. For information on
recommended tire pressure seeInation - Tire Pressure
on page 5-79andLoading Your Vehicle on page 4-48. Passenger (P-Metric) Tire
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(A) Tire Size:The tire size code is a combination of
letters and numbers used to dene 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.
(B) TPC Spec (Tire Performance Criteria
Specication):Original equipment tires designed to
GM’s specic tire performance criteria have a TPC
specication code molded onto the sidewall. GM’s
TPC specications meet or exceed all federal safety
guidelines.(C) Dual Tire Maximum Load:Maximum load that
can be carried and the maximum pressure needed to
support that load when used in a dual conguration.
For information on recommended tire pressure see
Ination - Tire Pressure on page 5-79andLoading
Your Vehicle on page 4-48.
(D) 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.
(E) Tire Identication Number (TIN):The letters and
numbers following DOT code are the Tire Identication
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.
(F) Tire Ply Material:The type of cord and number of
plies in the sidewall and under the tread.
(G) Single Tire Maximum Load:Maximum load that
can be carried and the maximum pressure needed to
support that load when used as a single. For information
on recommended tire pressure seeInation - Tire
Pressure on page 5-79andLoading Your Vehicle on
page 4-48. Light Truck (LT-Metric) Tire
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Tire Size
The following examples show the different parts of a
tire size.
(A) Passenger (P-Metric) Tire:The United States
version of a metric tire sizing system. The letter P as the
rst character in the tire size means a passenger vehicle
tire engineered to standards set by the U.S. Tire and Rim
Association.(A) Light Truck (LT-Metric) Tire:The United States
version of a metric tire sizing system. The letters LT as
the rst two characters in the tire size means a light
truck tire engineered to standards set by the U.S. Tire
and Rim Association.
(B) Tire Width:The three-digit number indicates the
tire section width in millimeters from sidewall to sidewall.
(C) Aspect Ratio:A two-digit number that indicates
the tire height-to-width measurements. For example,
if the tire size aspect ratio is 75, as shown in item C of
the light truck (LT-Metric) tire illustration, it would
mean that the tire’s sidewall is 75% as high as it is wide.
(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire.
The letter R means radial ply construction; the letter D
means diagonal or bias ply construction; and the letter B
means belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel in inches.
(F) Service Description:The service description
indicates the load range and speed rating of a tire.
The load index can range from 1 to 279. Speed ratings
range from A to Z. Passenger (P-Metric) Tire
Light Truck (LT-Metric) Tire
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How to Check
Use a good quality pocket-type gage to check tire
pressure. You cannot tell if your tires are properly
inated simply by looking at them. Radial tires may look
properly inated even when they’re underinated.
Check the tire’s ination pressure when the tires are
cold. Cold means your vehicle has been sitting
for at least three hours or driven no more than
1 mile (1.6 km).
Remove the valve cap from the tire valve stem. Press
the tire gage rmly onto the valve to get a pressure
measurement. If the cold tire ination pressure matches
the recommended pressure on the Tire and Loading
Information label, no further adjustment is necessary.
If the ination pressure is low, add air until you reach the
recommended amount.
If you overll the tire, release air by pushing on the
metal stem in the center of the tire valve. Recheck the
tire pressure with the tire gage.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and moisture.
Dual Tire Operation
When the vehicle is new, or whenever a wheel, wheel
bolt or wheel nut is replaced, check the wheel nut torque
after 100, 1,000 and 6,000 miles (160, 1 600 and
10 000 km) of driving. For proper torque and wheel nut
tightening information, seeRemoving the Spare Tire
and Tools on page 5-92.
The outer tire on a dual wheel setup generally wears
faster than the inner tire. Your tires will wear more evenly
and last longer if you rotate the tires periodically,
seeTire Inspection and Rotation on page 5-81. Also see
Scheduled Maintenance (Gasoline Engine) on page 6-4.
{CAUTION:
If you operate your vehicle with a tire that is
badly underinated, the tire can overheat. An
overheated tire can lose air suddenly or catch
re. You or others could be injured. Be sure all
tires (including the spare) are properly inated.
SeeInation - Tire Pressure on page 5-79, for
information on proper tire ination.
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Buying New Tires
GM has developed and matched specic tires for your
vehicle. The original equipment tires installed on
your vehicle, when it was new, were designed to meet
General Motors Tire Performance Criteria Specication
(TPC spec) system rating. If you need replacement
tires, GM strongly recommends that you get tires with
the same TPC Spec rating. This way, your vehicle
will continue to have tires that are designed to give the
same performance and vehicle safety, during normal
use, as the original tires.
GM’s exclusive TPC Spec system considers over a
dozen critical specications that impact the overall
performance of your vehicle, including brake system
performance, ride and handling, traction control, and tire
pressure monitoring performance. GM’s TPC Spec
number is molded onto the tire’s sidewall by the
tire manufacturer. If the tires have an all-season tread
design, the TPC spec number will be followed by an
MS for mud and snow. SeeTire Sidewall Labeling
on page 5-73for additional information.{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes,
brands or types (radial and bias-belted tires),
the vehicle may not handle properly, and you
could have a crash. Using tires of different
sizes, brands or types may also cause damage
to your vehicle. Be sure to use the same size,
brand, and type tires on all wheels.
Your vehicle may have a different size spare
than the road tires (those originally installed
on your vehicle). When new, your vehicle
included a spare tire and wheel assembly with
a similar overall diameter as your vehicle’s
road tires and wheels, so it is all right to drive
on it. Because this spare was developed for
use on your vehicle, it will not affect vehicle
handling.
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{CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rim anges could develop cracks after
many miles of driving. A tire and/or wheel
could fail suddenly, causing a crash. Use only
radial-ply tires with the wheels on your vehicle.
If you must replace your vehicle’s tires with those that
do not have a TPC Spec number, make sure they
are the same size, load range, speed rating, and
construction type (radial and bias-belted tires) as your
vehicle’s original tires.
Your vehicle’s original equipment tires are listed on the
Tire and Loading Information Label. This label is
attached to the vehicle’s center pillar (B-pillar). See
Loading Your Vehicle on page 4-48, for more information
about the Tire and Loading Information Label and its
location on your vehicle.
Different Size Tires and Wheels
If you add wheels or tires that are a different size than
your original equipment wheels and tires, this may
affect the way your vehicle performs, including its
braking, ride and handling characteristics, stability and
resistance to rollover. Additionally, if your vehicle
has electronic systems such as, antilock brakes; traction
control; and electronic stability control, the performance
of these systems can be affected.
{CAUTION:
If you add different sized wheels, your vehicle
may not provide an acceptable level of
performance and safety if tires not
recommended for those wheels are selected.
You may increase the chance that you will
crash and suffer serious injury. Only use GM
specic wheel and tire systems developed for
your vehicle, and have them properly installed
by a GM certied technician.
SeeBuying New Tires on page 5-84andAccessories
and Modications on page 5-4for additional information.
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