2007 CHEVROLET OPTRA 5 wheel

Brake Wear
Your vehicle has four-wheel disc 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 can come and go or be heard all
the time your vehicle is moving, except when you
are pushing on the brake pedal firmly.
{CAUTION:
The brake wear warning sound means that
soon the 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 can cause a
brake squeal when the brakes are first applied
or lightly applied. This does not mean something
is wrong with the brakes.
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
specifications.
Brake linings should always be replaced as
complete axle sets.
SeeBrake System Inspection on page 381.Brake Pedal Travel
See your dealer if the brake pedal does not return
to normal height, or if there is a rapid increase
in pedal travel. This could be a sign of brake
trouble.
Brake Adjustment
Every time you apply the brakes, with or without
the vehicle moving, the brakes adjust for wear.
283

Turn Signal Lamps (Side)
Your vehicle may have this side turn signal lamp.
It will be located between the front door and
the wheel well. To replace this bulb, do the
following:
1. Locate the bulb by reaching underneath the
vehicle where the side turn signal lamp is
located.
2. Remove the side turn signal lamp assembly
by pulling it forward.
3. Turn the bulb socket counterclockwise.
4. Remove the bulb from the lamp housing by
pulling the bulb straight out of the socket.
5. Install the new bulb into the bulb socket by
pushing it in and turning it clockwise.
6. Push the side turn signal lamp assembly back
into its original position.
293

(C) Aspect Ratio:A two-digit number that
indicates the tire height-to-width measurements.
For example, if the tire size aspect ratio is 70,
as shown in item C of the illustration, it would
mean that the tire’s sidewall is 70% 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 the speed rating
of a tire. The load range represents the load carry
capacity a tire is certified to carry. The speed
rating is the maximum speed a tire is certified to
carry a load. 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.
307

How to Check
Use a good quality pocket-type gage to check
tire pressure. You cannot tell if your tires are
properly inflated simply by looking at them. Radial
tires may look properly inflated even when they
are under-inflated. Check the tire’s inflation
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 firmly onto the valve to
get a pressure measurement. If the cold tire
inflation pressure matches the recommended
pressure on the Tire and Loading Information
label, no further adjustment is necessary. If the
inflation pressure is low, add air until you reach
the recommended amount.
If you overfill 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. If your vehicle has this feature, sensors
are mounted onto each tire and wheel assembly,
except for the spare tire. 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 inflated to
the inflation pressure recommended by the vehicle
manufacturer on the vehicle placard or tire
inflation pressure label. (If your vehicle has tires of
a different size than the size indicated on the
vehicle placard or tire inflation pressure label,
you should determine the proper tire inflation
pressure for those tires.)
312

As an added safety
feature, your vehicle
has been equipped
with a tire pressure
monitoring system
(TPMS) that illuminates
a low tire pressure
telltale when one
or more of your tires
is significantly
under-inflated.
Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires
as soon as possible, and inflate them to the
proper pressure. Driving on a significantly
under-inflated tire causes the tire to overheat and
can lead to tire failure. Under-inflation also
reduces fuel efficiency and tire tread life, and may
affect the vehicle’s handling and stopping ability.
Please note that the TPMS is not a substitute for
proper tire maintenance, and it is the driver’s
responsibility to maintain correct tire pressure, even
if under-inflation has not reached the level to trigger
illumination of the TPMS low tire pressure telltale.Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when the
system is not operating properly. The TPMS
malfunction indicator is combined with the low tire
pressure telltale. When the system detects a
malfunction, the telltale will flash for approximately
one minute and then remain continuously
illuminated. This sequence will continue upon
subsequent vehicle start-ups as long as the
malfunction exists.
When the malfunction indicator is illuminated, the
system may not be able to detect or signal low
tire pressure as intended. TPMS malfunctions may
occur for a variety of reasons, including the
installation of replacement or alternate tires or
wheels on the vehicle that prevent the TPMS from
functioning properly. Always check the TPMS
malfunction telltale after replacing one or more
tires or wheels on your vehicle to ensure that the
replacement or alternate tires and wheels allow
the TPMS to continue to function properly.
313

TPMS Sensor Identication Codes
Each TPMS sensor has a unique identification
code. Any time you replace one or more of
the TPMS sensors or rotate the vehicle’s tires, the
identification codes need to be matched to the
new tire/wheel position. The sensors are matched,
to the tire/wheel positions, in the following order:
driver side front tire, passenger side front tire,
passenger side rear tire, and driver side rear tire
using a TPMS diagnostic tool. See your dealer
for service.
Federal Communications Commission
(FCC) and Industry and Science Canada
The Tire Pressure Monitor System (TPMS)
operates on a radio frequency subject to Federal
Communications Commission (FCC) Rules
and with Industry and Science Canada.This device complies with Part 15 of the FCC
Rules. Operation is subject to the following
two conditions:
1. This device may not cause harmful
interference.
2. This device must accept any interference
received, including interference that may
cause undesired operation.
This device complies with RSS-210 of Industry
and Science Canada. Operation is subject to the
following two conditions:
1. This device may not cause interference.
2. This device must accept any interference
received, including interference that may
cause undesired operation of the device.
Changes or modifications to this system by other
than an authorized service facility could void
authorization to use this equipment.
315

Tire Inspection and Rotation
Tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km).
Any time you notice unusual wear, rotate your
tires as soon as possible and check wheel
alignment. Also check for damaged tires or wheels.
SeeWhen It Is Time for New Tires on page 317
andWheel Replacement on page 322for
more information.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The
first rotation is the most important. SeePart A:
Scheduled Maintenance Services on page 358.When rotating your tires, always use the correct
rotation pattern shown here.
Do not include the compact spare tire in the tire
rotation.
After the tires have been rotated, adjust the front
and rear inflation pressures as shown on the
tire and loading information label. SeeLoading
Your Vehicle on page 236for an example of
the tire and loading information label and where it
is located on your vehicle.
316

Make certain that all wheel nuts are properly
tightened. See “Wheel Nut Torque” under
Capacities and Specifications on page 352.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after time. The wheel could
come off and cause an accident. When
you change a wheel, remove any rust or
dirt from places where the wheel attaches
to the vehicle. In an emergency, you can
use a cloth or a paper towel to do this;
but be sure to use a scraper or wire brush
later, if needed, to get all the rust or dirt
off. SeeChanging a Flat Tire on page 324.
When It Is Time for New Tires
One way to tell when it
is time for new tires is
to check the treadwear
indicators, which will
appear when your tires
have only 1/16 inch
(1.6 mm) or less of tread
remaining.
You need a new tire if any of the following
statements are true:
•You can see the indicators at three or more
places around the tire.
•You can see cord or fabric showing through
the tire’s rubber.
•The tread or sidewall is cracked, cut, or
snagged deep enough to show cord or fabric.
•The tire has a bump, bulge, or split.
•The tire has a puncture, cut, or other damage
that cannot be repaired well because of the
size or location of the damage.
317