2006 GMC SIERRA 1500 Owners Manual

Intended Outboard Sidewall:The side of an
asymmetrical tire, that must always face outward when
mounted on a vehicle.
Kilopascal (kPa):The metric unit for air pressure.
Light Truck (LT-Metric) Tire:A tire used on light duty
trucks and some multipurpose passenger vehicles.
Load Index:An assigned number ranging from 1 to 279
that corresponds to the load carrying capacity of a tire.
Maximum Ination Pressure:The maximum air
pressure to which a cold tire may be inated. The
maximum air pressure is molded onto the sidewall.
Maximum Load Rating:The load rating for a tire at the
maximum permissible ination 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 150 lbs (68 kg).
SeeLoading Your Vehicle on page 4-48.
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 Ination Pressure:Vehicle
manufacturer’s recommended tire ination pressure and
shown on the tire placard. SeeInation - Tire Pressure
on page 5-79andLoading Your Vehicle on page 4-48.
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.
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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 1/16 inch (1.6 mm) of tread remains.
SeeWhen It Is Time for New Tires on page 5-83.
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. SeeUniform
Tire Quality Grading on page 5-86.Vehicle Capacity Weight:The number of designated
seating positions multiplied by 150 lbs (68 kg) plus
the rated cargo load. SeeLoading Your Vehicle
on page 4-48.
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’s capacity weight and
the original equipment tire size and recommended
ination pressure. See “Tire and Loading Information
Label” underLoading Your Vehicle on page 4-48.
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Ination - Tire Pressure
Tires need the correct amount of air pressure to operate
effectively.
Notice:Do not let anyone tell you that
under-ination or over-ination is all right. It is not.
If your tires do not have enough air (under-ination),
you can get the following:
Too much exing
Too much heat
Tire overloading
Premature or irregular wear
Poor handling
Reduced fuel economy
If your tires have too much air (over-ination),
you can get the following:
Unusual wear
Poor handling
Rough ride
Needless damage from road hazardsA Tire and Loading Information label is attached to the
vehicle’s center pillar (B-pillar), below the driver’s
door lock post (striker). This label lists your vehicle’s
original equipment tires and their recommended cold tire
ination pressures. The recommended cold tire
ination pressure, shown on the label, is the minimum
amount of air pressure needed to support your vehicle’s
maximum load carrying capacity.
For additional information regarding how much weight
your vehicle can carry, and an example of the tire
and loading information label, seeLoading Your Vehicle
on page 4-48.
When to Check
Check your tires once a month or more. Do not forget to
check the spare tire. For additional information
regarding the spare tire, seeSpare Tire on page 5-112.
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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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Tire Inspection and Rotation
Tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km).
Any time you notice unusual wear, rotate your tires as
soon as possible and check wheel alignment. Also
check for damaged tires or wheels. SeeWhen It Is Time
for New Tires on page 5-83andWheel Replacement
on page 5-87for more information.
Make sure the spare tire is stored securely. Push, pull,
and then try to rotate or turn the tire. If it moves,
use the wheel wrench/hoist shaft to tighten the cable.
SeeChanging a Flat Tire on page 5-91.
If your vehicle has dual rear wheels, also seeDual Tire
Operation on page 5-80.The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The rst rotation
is the most important. SeeScheduled Maintenance
(Gasoline Engine) on page 6-4.
If your vehicle has single rear wheels and the tread
design for your front tires is the same as your rear tires,
use the rotation pattern shown here when rotating
your tires.
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If your vehicle has dual rear wheels and the tread
design for your front tires is the same as your rear tires,
always use one of the correct rotation patterns shown
here when rotating your tires.If your vehicle has dual
rear wheels and the tread
design for the front
tires is different from the
dual rear tires, always use
the correct rotation
pattern shown here when
rotating your tires.
The dual tires are rotated as a pair, and the inside rear
tires become the outside rear tires.
When you install dual wheels, be sure the vent holes in
the inner and outer wheels on each side are lined up.
After the tires have been rotated, adjust the front
and rear ination pressures as shown on the Tire and
Loading Information label. SeeLoading Your Vehicle on
page 4-48.
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Make certain that all wheel nuts are properly tightened.
See “Wheel Nut Torque” underCapacities and
Specications on page 5-133.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the vehicle.
In an emergency, you can use a cloth or a
paper towel to do this; but be sure to use a
scraper or wire brush later, if needed, to get all
the rust or dirt off. SeeChanging a Flat Tire on
page 5-91.
When It Is Time for New Tires
One way to tell when it is
time for new tires is to
check the treadwear
indicators, which will
appear when your tires
have only 1/16 inch
(1.6 mm) or less of
tread remaining.
Some commercial truck
tires may not have
treadwear indicators.
You need a new tire if any of the following statements
are true:
You can see the indicators at three or more places
around the tire.
You can see cord or fabric showing through the
tire’s rubber.
The tread or sidewall is cracked, cut or snagged
deep enough to show cord or fabric.
The tire has a bump, bulge, or split.
The tire has a puncture, cut, or other damage that
cannot be repaired well because of the size or
location of the damage.
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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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