2009 CHEVROLET TAHOE Owners Manual

(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 seeInflation - Tire Pressure on
page 5-70andLoading the Vehicle on page 4-33.
(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.
Light Truck (LT-Metric) Tire
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(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 seeInflation - Tire Pressure on
page 5-70andLoading the Vehicle on page 4-33.
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.Passenger (P-Metric) Tire
Light Truck (LT-Metric) Tire
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(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 percent 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 represents the load carry
capacity a tire is certied to carry. The load index
can range from 1 to 279. The speed rating is
the maximum speed a tire is certied to carry a
load. Speed ratings range from A to Z.
Tire Terminology and Denitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of the
tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
Aspect Ratio
:The relationship of a tire’s height
to its width.
Belt
:A rubber coated layer of cords that is
located between the plies and the tread. Cords
may be made from steel or other reinforcing
materials.
Bead
:The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.
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Cold Tire Pressure:The amount of air pressure in
a tire, measured in pounds per square inch (psi) or
kilopascals (kPa) before a tire has built up heat
from driving. SeeInflation - Tire Pressure on
page 5-70.
Curb Weight
:The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant,
but without passengers and cargo.
DOT Markings
:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identication Number (TIN),
an alphanumeric designator which can also identify
the tire manufacturer, production plant, brand,
and date of production.
GVWR
:Gross Vehicle Weight Rating. See
Loading the Vehicle on page 4-33.
GAWR FRT
:Gross Axle Weight Rating for the
front axle. SeeLoading the Vehicle on page 4-33.
GAWR RR
:Gross Axle Weight Rating for the
rear axle. SeeLoading the Vehicle on page 4-33.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 can 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 the Vehicle on
page 4-33.
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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
as shown on the tire placard. SeeInflation - Tire
Pressure on page 5-70andLoading the Vehicle on
page 4-33.
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.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 5-77.
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 5-80.
Vehicle Capacity Weight
:The number of
designated seating positions multiplied by 150 lbs
(68 kg) plus the rated cargo load. SeeLoading
the Vehicle on page 4-33.
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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 the Vehicle on
page 4-33.
Ination - Tire Pressure
If your vehicle is a Two-mode Hybrid, see the
Two-mode Hybrid manual for more information.
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 economyIf your tires have too much air (over-ination),
you can get the following:
Unusual wear
Poor handling
Rough ride
Needless damage from road hazards
A vehicle specic Tire and Loading Information
label is attached to your vehicle. This label shows
your vehicle’s original equipment tires and the
correct ination pressures for your tires when they
are cold. 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
the Vehicle on page 4-33. How you load your
vehicle affects vehicle handling and ride comfort.
Never load your vehicle with more weight than it
was designed to carry.
When to Check
Check your tires once a month or more.
Do not forget to check the pressure of the spare
tire. SeeSpare Tire on page 5-105for additional
information.
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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 are
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 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.
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
vehicle’s 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 inated to the ination
pressure recommended by the vehicle manufacturer
on the vehicle placard or tire ination pressure label.
(If your vehicle has tires of a different size than the size
indicated on the vehicle placard or tire ination
pressure label, you should determine the proper tire
ination 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 signicantly under-inated.
Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires as soon
as possible, and inate them to the proper pressure.
Driving on a signicantly under-inated tire causes the
tire to overheat and can lead to tire failure. Under-ination
also reduces fuel efficiency and tire tread life, and may
affect the vehicle’s handling and stopping ability.
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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-ination 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
ash for approximately one minute and then remain
continuously illuminated. This sequence will continue
upon subsequent vehicle start-ups as long as the
malfunction exists.
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 5-73for
additional information.Federal Communications Commission
(FCC) and Industry and Science Canada
The Tire Pressure Monitor System (TPMS) operates
on a radio frequency and complies with Part 15 of
the FCC Rules. Operation is subject to the following
two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation.
The TPMS operates on a radio frequency and complies
with RSS-210 of Industry and Science Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
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