Brake Wear
Your vehicle has front disc brakes and rear drum
brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched warning sound when the brake pads
are worn and new pads are needed. The sound
may come and go or be heard all the time your vehicle
is moving, except when you are pushing on the
brake pedal rmly.
{CAUTION:
The brake wear warning sound means that
soon your brakes will not work well. That
could lead to an accident. When you hear the
brake wear warning sound, have your vehicle
serviced.
Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.Some driving conditions or climates may cause a
brake squeal when the brakes are rst applied or lightly
applied. This does not mean something is wrong with
your brakes.
SeeCaliper/Knuckle Maintenance Inspection on
page 6-23.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to GM torque speci cations.
Your rear drum brakes do not have wear indicators,
but if you ever hear a rear brake rubbing noise, have the
rear brake linings inspected immediately. Also, the
rear brake drums should be removed and inspected
each time the tires are removed for rotation or changing.
When you have the front brake pads replaced, have
the rear brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
SeeBrake System Inspection on page 6-23.
5-34
Notice:If you leave your radio or other accessories
on during the jump starting procedure, they could
be damaged. The repairs would not be covered
by your warranty. Always turn off your radio and
other accessories when jump starting your vehicle.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or the accessory power outlet. Turn off
the radio and all lamps that are not needed. This
will avoid sparks and help save both batteries.
And it could save the radio!
4. Open the hoods and locate the batteries. Find the
positive (+) and negative (−) terminal locations on
each vehicle. SeeEngine Compartment Overview
on page 5-12for more information on location.
{CAUTION:
An electric fan can start up even when the
engine is not running and can injure you.
Keep hands, clothing and tools away from
any underhood electric fan.
{CAUTION:
Using a match near a battery can cause battery
gas to explode. People have been hurt doing
this, and some have been blinded. Use a
ashlight if you need more light.
Be sure the battery has enough water. You do
not need to add water to the battery installed
in your new vehicle. But if a battery has ller
caps, be sure the right amount of uid is there.
If it is low, add water to take care of that rst.
If you don’t, explosive gas could be present.
Battery uid contains acid that can burn you.
Do not get it on you. If you accidentally get it
in your eyes or on your skin, ush the place
with water and get medical help immediately.
5-38
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.
Cold In ation 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. SeeIn ation - Tire Pressure on page 5-53.
Curb Weight:This means 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 Identi cation Number (TIN), an alphanumeric
designator which can also identify the tire manufacturer,
production plant, brand and date of production.
GVWR:Gross Vehicle Weight Rating, seeLoading
Your Vehicle on page 4-29.GAWR FRT:Gross Axle Weight Rating for the front
axle, seeLoading Your Vehicle on page 4-29.
GAWR RR:Gross Axle Weight Rating for the rear axle,
seeLoading Your Vehicle on page 4-29.
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 In ation Pressure:The maximum air
pressure to which a cold tire may be in ated. The
maximum air pressure is molded onto the sidewall.
Maximum Load Rating:The load rating for a tire at the
maximum permissible in ation 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 Your Vehicle on page 4-29.
5-51
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 In ation Pressure:Vehicle
manufacturer’s recommended tire in ation pressure and
shown on the tire placard. SeeIn ation - Tire Pressure
on page 5-53andLoading Your Vehicle on page 4-29.
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. See
When It Is Time for New Tires on page 5-55.
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 5-57.
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 4-29.
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 original equipment tire size and
recommended in ation pressure. SeeLoading Your
Vehicle on page 4-29.
5-52
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, 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
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.
While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a speci ed government test course.
For example, a tire graded 150 would wear one and
a half (1.5) times as well on the government course as
a tire graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart signi cantly from the norm
due to variations in driving habits, service practices and
differences in road characteristics and climate.
Traction – AA, A, B, C
The traction grades, from highest to lowest, are AA, A,
B, and C. Those grades represent the tire’s ability
to stop on wet pavement as measured under controlled
conditions on speci ed government test surfaces of
asphalt and concrete. A tire marked C may have poor
traction performance. Warning: The traction grade
assigned to this tire is based on straight-ahead braking
traction tests, and does not include acceleration,
cornering, hydroplaning, or peak traction characteristics.
5-57