tire size CHEVROLET SILVERADO 2008 2.G Owners Manual

In addition, your vehicle may have a passenger
sensing system for the right front passenger’s
position, which includes sensors that are part of the
passenger’s seat. The passenger sensing system
may not operate properly if the original seat trim is
replaced with non-GM covers, upholstery or trim, or
with GM covers, upholstery or trim designed for a
different vehicle. Any object, such as an aftermarket
seat heater or a comfort enhancing pad or device,
installed under or on top of the seat fabric, could also
interfere with the operation of the passenger sensing
system. This could either prevent proper deployment
of the passenger airbag(s) or prevent the passenger
sensing system from properly turning off the
passenger airbag(s). SeePassenger Sensing
System on page 1-81.
If you have any questions about this, you should
contact Customer Assistance before you modify
your vehicle. The phone numbers and addresses
for Customer Assistance are in Step Two of
the Customer Satisfaction Procedure in this manual.
SeeCustomer Satisfaction Procedure on page 7-2.
If your vehicle has rollover roof-rail airbags, see
Different Size Tires and Wheels on page 5-88
for additional important information.Q:What if I added a snow plow? Will it keep the
airbags from working properly?
A:We have designed our airbag systems to work
properly under a wide range of conditions, including
snow plowing with vehicles that have the optional
Snow Plow Prep Package (RPO VYU). But do
not change or defeat the snow plow’s “tripping
mechanism.” If you do, it can damage your snow
plow and your vehicle, and it may cause an airbag
ination.
Q:Because I have a disability, I have to get my
vehicle modied. How can I nd out whether
this will affect my airbag system?
A:If you have questions, call Customer Assistance.
The phone numbers and addresses for Customer
Assistance are in Step Two of the Customer
Satisfaction Procedure in this manual. See
Customer Satisfaction Procedure on page 7-2.
In addition, your dealer/retailer and the service manual
have information about the location of the airbag
sensors, sensing and diagnostic module and airbag
wiring.
1-87

The Tire and Loading Information label also shows
the size of the original equipment tires (C) and
the recommended cold tire ination pressures (D).
For more information on tires and ination see
Tires on page 5-68andInflation - Tire Pressure on
page 5-76.
There is also important loading information on the
vehicle Certication/Tire label. It tells you the
Gross Vehicle Weight Rating (GVWR) and
the Gross Axle Weight Rating (GAWR) for the
front and rear axles. See “Certication/Tire Label”
later in this section.
Steps for Determining Correct Load Limit
1.Locate the statement “The combined weight of
occupants and cargo should never exceed
XXX kg or XXX lbs” on your vehicle’s placard.
2.Determine the combined weight of the driver
and passengers that will be riding in your
vehicle.
3.Subtract the combined weight of the driver
and passengers from XXX kg or XXX lbs.
4.The resulting gure equals the available
amount of cargo and luggage load capacity.
For example, if the “XXX” amount equals
1400 lbs and there will be ve 150 lb
passengers in your vehicle, the amount of
available cargo and luggage load capacity is
650 lbs (1400−750 (5 x 150) = 650 lbs).
5.Determine the combined weight of luggage
and cargo being loaded on the vehicle. That
weight may not safely exceed the available
cargo and luggage load capacity calculated
in Step 4.
6.If your vehicle will be towing a trailer, the load
from your trailer will be transferred to your
vehicle. Consult this manual to determine how
this reduces the available cargo and luggage
load capacity of your vehicle. SeeTowing
a Trailer on page 4-55for important
information on towing a trailer, towing safety
rules and trailering tips.
4-37

Item Description Total
AVehicle Capacity
Weight for
Example 3=1,000 lbs
(453 kg)
BSubtract Occupant
Weight 200 lbs
(91 kg)×5=1000 lbs
(453 kg)
CAvailable Cargo
Weight=0 lbs (0 kg)
Refer to your vehicle’s tire and loading information
label for specic information about your vehicle’s
capacity weight and seating positions.The combined weight of the driver, passengers,
and cargo should never exceed your vehicle’s
capacity weight.
Certication/Tire Label
A vehicle specic Certication/Tire label is found
on the rear edge of the driver’s door. The label
shows the size of your vehicle’s original tires and
the ination pressures needed to obtain the
gross weight capacity of your vehicle. This is called
Gross Vehicle Weight Rating (GVWR).
Example 3
4-39

Bulb Replacement..........................................5-61
Halogen Bulbs..............................................5-61
Headlamps..................................................5-62
Center High-Mounted Stoplamp (CHMSL) and
Cargo Lamp.............................................5-63
Pickup Box Identication and
Fender Marker Lamps................................5-64
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps.........................................5-64
License Plate Lamp......................................5-66
Replacement Bulbs.......................................5-66
Windshield Wiper Blade Replacement..............5-67
Tires..............................................................5-68
Tire Sidewall Labeling...................................5-69
Tire Terminology and Denitions.....................5-73
Ination - Tire Pressure.................................5-76
Dual Tire Operation.......................................5-77
Tire Pressure Monitor System.........................5-78
Tire Pressure Monitor Operation.....................5-79
Tire Inspection and Rotation...........................5-83
When It Is Time for New Tires.......................5-86
Buying New Tires.........................................5-86
Different Size Tires and Wheels......................5-88
Uniform Tire Quality Grading..........................5-89Wheel Alignment and Tire Balance..................5-90
Wheel Replacement......................................5-90
Tire Chains..................................................5-92
If a Tire Goes Flat........................................5-93
Changing a Flat Tire.....................................5-94
Removing the Spare Tire and Tools................5-95
Removing the Flat Tire and Installing the
Spare Tire..............................................5-100
Secondary Latch System..............................5-106
Storing a Flat or Spare Tire and Tools...........5-110
Spare Tire.................................................5-113
Appearance Care..........................................5-114
Interior Cleaning.........................................5-114
Fabric/Carpet..............................................5-115
Leather......................................................5-116
Instrument Panel, Vinyl, and Other Plastic
Surfaces.................................................5-117
Care of Safety Belts....................................5-117
Weatherstrips.............................................5-117
Washing Your Vehicle..................................5-118
Cleaning Exterior Lamps/Lenses....................5-118
Finish Care................................................5-119
Windshield and Wiper Blades.......................5-120
Aluminum or Chrome-Plated Wheels
and Trim................................................5-120
Section 5 Service and Appearance Care
5-2

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.
{CAUTION:
Poorly maintained and improperly used
tires are dangerous.
Overloading your vehicle’s tires can
cause overheating as a result of too
much exing. You could have an air-out
and a serious accident. SeeLoading
Your Vehicle on page 4-36.
Underinated tires pose the same
danger as overloaded tires. The
resulting accident could cause serious
injury. Check all tires frequently to
maintain the recommended pressure.
Tire pressure should be checked when
your vehicle’s tires are cold. See
Inflation - Tire Pressure on page 5-76.
CAUTION: (Continued)
CAUTION: (Continued)

Overinated tires are more likely to
be cut, punctured, or broken by a
sudden impact — such as when you
hit a pothole. Keep tires at the
recommended pressure.
Worn, old tires can cause accidents.
If the tire’s tread is badly worn,
or if your vehicle’s tires have been
damaged, replace them.
20-Inch Tires
If your vehicle has the optional 20-inch
P275/55R20 size tires, they are classied as
touring tires and are designed for on road use.
The low-prole, wide tread design is not
recommended for “off-road” driving or commercial
uses such as snow plowing. SeeOff-Road
Driving on page 4-12andAdding a Snow Plow or
Similar Equipment on page 4-43for additional
information.
5-68

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.
Passenger (P-Metric) Tire
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(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, seeUniform Tire Quality
Grading on page 5-89.
(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
seeInflation - Tire Pressure on page 5-76
andLoading Your Vehicle on page 4-36.
(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.
Light Truck (LT-Metric) Tire
5-70

(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 5-76andLoading Your Vehicle on page 4-36.
(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 see
Inflation - Tire Pressure on page 5-76andLoading
Your Vehicle on page 4-36.
5-71

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 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 can range from 1 to 279.
Speed ratings range from A to Z.
Passenger (P-Metric) Tire
Light Truck (LT-Metric) Tire
5-72

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 5-86.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 5-89.
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 4-36.
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 4-36.
5-75