Page 410 of 528

(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 range and speed rating of the
tire. The load index represents the load carry
capacity a tire is certi ed to carry. The load index
can range from 1 to 279. The speed rating is
the maximum speed a tire is certi ed to carry a
load. Speed ratings range from A to Z.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/
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.
410
Page 420 of 528

Different Size Tires and Wheels
If you add wheels or tires that are a different size
than your original equipment wheels and tires, this
may affect the way your vehicle performs, including
its braking, ride and handling characteristics,
stability, and resistance to rollover. Additionally,
if your vehicle has electronic systems such as,
anti-lock brakes, traction control, and electronic
stability control, the performance of these systems
can be affected.
{CAUTION:
If you add different sized wheels, your
vehicle may not provide an acceptable
level of performance and safety if tires
not recommended for those wheels are
selected. You may increase the chance
that you will crash and suffer serious
injury. Only use GM speci c wheel and
tire systems developed for your vehicle,
and have them properly installed by a GM
certi ed technician.SeeBuying New Tires on page 418and
Accessories and Modi cations on page 354
for additional information.
Uniform Tire Quality Grading
Quality grades can be found where applicable
on the tire sidewall between tread shoulder
and maximum section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration (NHTSA), which
grades tires by treadwear, traction, and
temperature performance. This applies only to
vehicles sold in the United States. The grades are
molded on the sidewalls of most passenger car
tires. The Uniform Tire Quality Grading (UTQG)
system does not apply to deep tread, winter-type
snow tires, space-saver, or temporary use spare
tires, tires with nominal rim diameters of
10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
420
Page 424 of 528
Tire Chains
{CAUTION:
Do not use tire chains. There is not enough
clearance. Tire chains used on a vehicle
without the proper amount of clearance
can cause damage to the brakes,
suspension, or other vehicle parts. The
area damaged by the tire chains could
cause you to lose control of your vehicle
and you or others may be injured in a
crash.
CAUTION: (Continued)
CAUTION: (Continued)
Use another type of traction device only if
its manufacturer recommends it for use
on your vehicle and tire size combination
and road conditions. Follow that
manufacturer’s instructions. To help avoid
damage to your vehicle, drive slowly,
readjust or remove the device if it is
contacting your vehicle, and do not spin
the wheels. If you do nd traction devices
that will t, install them on the front tires
for front-wheel-drive vehicles. If your
vehicle has all-wheel drive, install traction
devices on either the front tires or all four
tires, but never on the rear tires only.
424
Page 510 of 528
Service Publications Ordering
Information
Service Manuals
Service Manuals have the diagnosis and repair
information on engines, transmission, axle
suspension, brakes, electrical, steering, body, etc.
Transmission, Transaxle, Transfer
Case Unit Repair Manual
This manual provides information on unit repair
service procedures, adjustments, and
speci cations for GM transmissions, transaxles,
and transfer cases.
Service Bulletins
Service Bulletins give technical service information
needed to knowledgeably service General Motors
cars and trucks. Each bulletin contains instructions
to assist in the diagnosis and service of your
vehicle.
In Canada, the service bulletin reference number
can be obtained by contacting your General
Motors dealer or by calling 1-800-GM-DRIVE
(1-800-463-7483). This reference number is
needed to order the service bulletin from
Helm, Inc.
RETAIL SELL PRICE: $6.00 US + Processing Fee
510
Page 514 of 528

Ashtray(s).................................................... 200
Audio System(s).......................................... 250
Audio Steering Wheel Controls................. 296
Care of Your CD and DVD Player............ 298
Care of Your CDs and DVDs................... 298
Fixed Mast Antenna................................. 299
Navigation/Radio System, see
Navigation Manual................................ 277
Radio with CD......................................... 252
Radio with Six-Disc CD............................ 262
Rear Seat Audio (RSA)............................ 293
Setting the Time...................................... 252
Theft-Deterrent Feature............................ 296
Understanding Radio Reception............... 297
XM™ Satellite Radio Antenna System...... 299
Automatic Headlamp System....................... 187
Automatic Transaxle
Fluid........................................................ 372
Operation................................................. 132
B
Battery........................................................ 393
Run-Down Protection............................... 192
Before Leaving on a Long Trip.................... 323
Bench Seat, Split.......................................... 15Brake
Anti-Lock Brake System (ABS)................. 307
Emergencies............................................ 309
Low Fluid Warning Message.................... 232
Parking.................................................... 135
System Warning Light.............................. 219
Brakes........................................................ 389
Braking....................................................... 306
Braking in Emergencies............................... 309
Break-In, New Vehicle................................. 127
Bulb Replacement....................................... 399
Halogen Bulbs......................................... 399
Headlamps, Front Turn Signal,
Sidemarker, and Parking Lamps........... 399
Replacement Bulbs.................................. 404
Taillamps and Back-Up Lamps................. 402
Taillamps, Turn Signal, and Stoplamps..... 401
Buying New Tires........................................ 418
C
Calibration................................................... 238
California Fuel............................................. 357
California Proposition 65 Warning................ 355
Canadian Owners........................................... 3
Capacities and Speci cations...................... 469
Captain Chairs, Rear..................................... 21
514