(A) Temporary Use Only:The
compact spare tire or temporary
use tire has a tread life of
approximately 3,000 miles
(5 000 km) and should not be
driven at speeds over 65 mph
(105 km/h). The compact spare
tire is for emergency use when a
regular road tire has lost air and
gone at. If your vehicle has a
compact spare tire, seeCompact
Spare Tire on page 5-83andIf a
Tire Goes Flat on page 5-61.(B) Tire Ply Material
:The type
of cord and number of plies in the
sidewall and under the tread.
(C) Tire Identi cation Number
(TIN)
:The letters and numbers
following the DOT (Department
of Transportation) code is the
Tire Identi cation 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.
(D) Maximum Cold In ation
Load Limit
:Maximum load that
can be carried and the maximum
pressure needed to support
that load.(E) Tire In ation
:The
temporary use tire or compact
spare tire should be in ated to
60 psi (420 kPa). For more
information on tire pressure and
in ation seeInflation - Tire
Pressure on page 5-45.
(F) Tire Size
:A combination of
letters and numbers de ne a
tire’s width, height, aspect ratio,
construction type, and service
description. The letter T as the
rst character in the tire size
means the tire is for temporary
use only.
(G) TPC Spec (Tire
Performance Criteria
Speci cation)
:Original
equipment tires designed to
GM’s speci c tire performance
criteria have a TPC speci cation
code molded onto the sidewall.
GM’s TPC speci cations meet
or exceed all federal safety
guidelines. Compact Spare Tire Example
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Tire Size
The following illustration shows
an example of a typical
passenger vehicle 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.
(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 60, as shown in
item C of the illustration, it would
mean that the tire’s sidewall is
60 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
:These
characters represent the load
index and speed rating of the tire.
The load index represents the
load carry capacity a tire is
certi ed to carry. The speed
rating is the maximum speed a
tire is certi ed to carry a load.
Tire Terminology and
De nitions
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.
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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 4-18.
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 in ation
pressure. See “Tire and Loading
Information Label” underLoading
the Vehicle on page 4-18.
In ation - Tire Pressure
Tires need the correct amount
of air pressure to operate
effectively.
Notice:Do not let anyone tell
you that under-in ation or
over-in ation is all right. It is
not. If your tires do not have
enough air (under-in ation),
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-in ation), you can get
the following:
Unusual wear
Poor handling
Rough ride
Needless damage from road
hazardsA vehicle speci c Tire and
Loading Information label is
attached to your vehicle. This
label shows your vehicle’s
original equipment tires and the
correct in ation pressures for
your tires when they are cold.
The recommended cold tire
in ation 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 4-18. How
you load your vehicle affects
vehicle handling and ride
comfort. Never load your vehicle
with more weight than it was
designed to carry.
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When to Check
Check your tires once a month
or more. Do not forget to check
the compact spare tire, if the
vehicle has one. It should be at
60 psi (420 kPa). For additional
information regarding the
compact spare tire, seeCompact
Spare Tire on page 5-83.
How to Check
Use a good quality pocket-type
gage to check tire pressure.
You cannot tell if your tires are
properly in ated simply by
looking at them. Radial tires may
look properly in ated even when
they are under-in ated. Check
the tire’s in ation 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 in ation pressure
matches the recommended
pressure on the Tire and Loading
Information label, no further
adjustment is necessary. If the
in ation pressure is low, add air
until you reach the recommended
amount.
If you over ll the tire, release
air by pushing on the metal stem
in the center of the tire valve.
Re-check 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 in ated to the
in ation pressure recommended by
the vehicle manufacturer on the
vehicle placard or tire in ation
pressure label. (If your vehicle has
tires of a different size than the size
indicated on the vehicle placard or
tire in ation pressure label, you
should determine the proper tire
in ation pressure for those tires.)
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When a low tire pressure condition is
detected, the TPMS illuminates the
low tire pressure warning light
located on the instrument panel
cluster.
At the same time a message to
check the pressure in a speci c tire
appears on the Driver Information
Center (DIC) display. The low tire
pressure warning light and the DIC
warning message come on at each
ignition cycle until the tires are
in ated to the correct in ation
pressure. Using the DIC, tire
pressure levels can be viewed by the
driver. For additional information and
details about the DIC operation and
displays seeDIC Operation and
Displays (With DIC Buttons) on
page 3-45orDIC Operation andDisplays (Without DIC Buttons) on
page 3-50andDIC Warnings and
Messages on page 3-56.
The low tire pressure warning light
may come on in cool weather
when the vehicle is rst started, and
then turn off as you start to drive.
This could be an early indicator that
the air pressure in the tire(s) are
getting low and need to be in ated
to the proper pressure.
A Tire and Loading Information
label, attached to your vehicle,
shows the size of your vehicle’s
original equipment tires and
the correct in ation pressure for
your vehicle’s tires when they
are cold. SeeLoading the Vehicle
on page 4-18, for an example of the
Tire and Loading Information
label and its location on your
vehicle. Also seeInflation - Tire
Pressure on page 5-45.Your vehicle’s TPMS can warn you
about a low tire pressure condition
but it does not replace normal
tire maintenance. SeeTire
Inspection and Rotation on
page 5-52andTires on page 5-39.
Notice:Using non-approved tire
sealants could damage the Tire
Pressure Monitor System (TPMS)
sensors. TPMS sensor damage
caused by using an incorrect tire
sealant is not covered by the
vehicle warranty. Always use the
GM approved tire sealant available
through your dealer/retailer.
Factory-installed Tire In ator Kits
use a GM approved liquid tire
sealant. Using non-approved tire
sealants could damage the TPMS
sensors. SeeTire Sealant and
Compressor Kit on page 5-62for
information regarding the in ator kit
materials and instructions.
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