tire size GMC SIERRA CLASSIC 2007 Owners Manual

RDS Messages
INFO (Information):If the current station has a
message, INFO 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 this button. Once the
complete message has been displayed, INFO 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 dealer for service.LOCKED:This message is displayed when the
THEFTLOCK
®system has locked up. Take
the vehicle to your dealer for service.
If any error occurs repeatedly, or if an error cannot
be corrected, contact your GM dealer.
Radio Messages for XM™ Only
SeeXM Radio Messages on page 332later in this
section for further detail.
Playing a CD
If the ignition or radio is turned off, with a CD in
the player, it will stay in the player. When the
ignition or radio is turned on, the CD will
start playing where it stopped, if it was the last
selected audio source.
When a CD is inserted, the CD symbol will appear
on the display. As each new track starts to play,
the track number will appear on the display.
The CD player can play the smaller 3 inch (8 cm)
single CDs with an adapter ring. Full-size CDs
and the smaller CDs are loaded in the same
manner.
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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 543andInation - Tire Pressure on
page 551.
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 429for important information
on towing a trailer, towing safety rules and
trailering tips.
410

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).
The GVWR includes the weight of the vehicle,
all occupants, fuel, and cargo.
The Certication/Tire label also tells you the
maximum weights for the front and rear axles,
called Gross Axle Weight Rating (GAWR).
Example 3
412

Noise Control System................................. 531
Tampering with Noise Control System
Prohibited.............................................. 531
Bulb Replacement....................................... 532
Halogen Bulbs........................................... 532
Headlamps................................................ 533
Front Turn Signal, Sidemarker and
Daytime Running Lamps........................ 534
Roof Marker Lamps................................... 535
Center High-Mounted Stoplamp (CHMSL)
and Cargo Lamp.................................... 537
Pickup Box Identication and Fender
Marker Lamps........................................ 538
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps...................................... 539
License Plate Lamp................................... 541
Replacement Bulbs................................... 541
Windshield Wiper Blade Replacement....... 542
Tires............................................................ 543
Tire Sidewall Labeling............................... 544
Tire Terminology and Denitions............... 548
Ination - Tire Pressure............................. 551
Dual Tire Operation................................... 552Tire Inspection and Rotation...................... 553
When It Is Time for New Tires.................. 555
Buying New Tires...................................... 556
Different Size Tires and Wheels................ 558
Uniform Tire Quality Grading..................... 559
Wheel Alignment and Tire Balance............ 560
Wheel Replacement.................................. 560
Tire Chains............................................... 562
If a Tire Goes Flat.................................... 563
Changing a Flat Tire................................. 564
Removing the Spare Tire and Tools.......... 566
Removing the Flat Tire and Installing
the Spare Tire....................................... 571
Secondary Latch System........................... 580
Storing a Flat or Spare Tire and Tools...... 584
Spare Tire................................................. 588
Appearance Care........................................ 589
Cleaning the Inside of Your Vehicle.......... 589
Fabric/Carpet............................................. 590
Leather...................................................... 591
Instrument Panel, Vinyl, and Other
Plastic Surfaces..................................... 591
Care of Safety Belts.................................. 592
Weatherstrips............................................ 592
Section 5 Service and Appearance Care
466

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 372andAdding a Snow Plow or Similar
Equipment on page 416for additional information.
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.
Passenger (P-Metric) Tire
544

(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, seeUniform Tire Quality Grading on
page 559.
(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 see
Ination - Tire Pressure on page 551andLoading
Your Vehicle on page 409.
545

(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 seeInation - Tire Pressure on
page 551andLoading Your Vehicle on page 409.
(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
546

(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 551andLoading Your Vehicle on page 409.
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
547

(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.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/
transaxle, 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.
548

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 409.
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 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 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, see
Loading Your Vehicle on page 409.
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 588.
551