service CHEVROLET EXPRESS 2008 Repair Manual

(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
seeInation - Tire Pressure on page 6-68
andLoading the Vehicle on page 5-19.(A) Tire Size:The tire size code is a combination
of letters and numbers used to define 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 specific tire performance criteria have a
TPC specification code molded onto the sidewall.
GM’s TPC specifications meet or exceed all federal
safety guidelines. This does not apply to Goodyear
LT225/75R16 G949 RSA and Goodyear LT225/
75R16 G933 RSD commercial truck tires.
(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
configuration. For information on recommended
tire pressure seeInation - Tire Pressure on
page 6-68andLoading the Vehicle on page 5-19.
(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.
Light Truck (LT-Metric) Tire
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(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 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
:These characters
represent the load index and speed rating of the
tire. The load index 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.(A) Light Truck (LT-Metric) Tire
:The United
States version of a metric tire sizing system.
The letters LT as the first 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.
Light Truck (LT-Metric) Tire
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(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) Load Range
:Load Range.
(G) Service Description
:The service description
indicates the load index and speed rating of a tire.
If two numbers are given as in the example,
120/116, then this represents the load index for
single versus dual wheel usage (single/dual).
The speed rating is the maximum speed a tire is
certified to carry a load. This does not apply to
Goodyear LT225/75R16 G949 RSA and Goodyear
LT225/75R16 G933 RSD commercial truck tires;
see the dual tire and single tire maximum load and
load range letter designations on the tire sidewall.
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,
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.
6-65

TPMS Malfunction Light and Message
The TPMS will not function properly if one or more of the
TPMS sensors are missing or inoperable. When the
system detects a malfunction, the low tire warning light
flashes for about one minute and then stays on for the
remainder of the ignition cycle. A DIC warning message
is also displayed. The low tire warning light and DIC
warning message come on at each ignition cycle until
the problem is corrected. Some of the conditions that
can cause the malfunction light and DIC message to
come on are:
•One of the road tires has been replaced with the
spare tire. The spare tire does not have a TPMS
sensor. The TPMS malfunction light and DIC
message should go off once you re-install the
road tire containing the TPMS sensor.
•The TPMS sensor matching process was started but
not completed or not completed successfully after
rotating the vehicle’s tires. The DIC message and
TPMS malfunction light should go off once the TPMS
sensor matching process is performed successfully.
See “TPMS Sensor Matching Process” later in this
section.
•One or more TPMS sensors are missing or
damaged. The DIC message and the TPMS
malfunction light should go off when the TPMS
sensors are installed and the sensor matching
process is performed successfully. See your
dealer/retailer for service.
•Replacement tires or wheels do not match your
vehicle’s original equipment tires or wheels. Tires
and wheels other than those recommended for your
vehicle could prevent the TPMS from functioning
properly. SeeBuying New Tires on page 6-79.
•Operating electronic devices or being near facilities
using radio wave frequencies similar to the TPMS
could cause the TPMS sensors to malfunction.
If the TPMS is not functioning it cannot detect or
signal a low tire condition. See your dealer/retailer for
service if the TPMS malfunction light and DIC message
comes on and stays on.
6-73

TPMS Sensor Matching Process
Each TPMS sensor has a unique identification code.
Any time you rotate your vehicle’s tires or replace one
or more of the TPMS sensors, the identification codes
will 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/retailer for
service.
The TPMS sensors can also be matched to each
tire/wheel position by increasing or decreasing the
tire’s air pressure. If increasing the tire’s air pressure,
do not exceed the maximum inflation pressure indicated
on the tire’s sidewall.
To decrease air-pressure out of a tire you can use the
pointed end of the valve cap, a pencil-style air pressure
gage, or a key.
You have two minutes to match the first tire/wheel
position, and five minutes overall to match all four
tire/wheel positions. If it takes longer than two minutes, to
match the first tire and wheel, or more than five minutes
to match all four tire and wheel positions the matching
process stops and you need to start over.The TPMS sensor matching process is outlined below:
1. Set the parking brake.
2. Turn the ignition switch to ON/RUN with the
engine off.
3. Press the Remote Keyless Entry (RKE) transmitter’s
LOCK and UNLOCK buttons at the same time
for approximately five seconds. The horn sounds
twice to signal the receiver is in relearn mode and
TIRE LEARNING ACTIVE message displays on the
DIC screen.
If your vehicle does not have RKE, press the Driver
Information Center (DIC) vehicle information button
until the PRESS
VTO RELEARN TIRE POSITIONS
message displays. The horn sounds twice to signal
the receiver is in relearn mode and TIRE LEARNING
ACTIVE message displays on the DIC screen.
If your vehicle does not have RKE or DIC buttons,
press the trip odometer reset stem located on the
instrument panel cluster until the PRESS
VTO
RELEARN TIRE POSITIONS message displays.
The horn sounds twice to signal the receiver is in
relearn mode and TIRE LEARNING ACTIVE
message displays on the DIC screen.
6-74

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.
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 specified 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 significantly 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 specified government test
surfaces of asphalt and concrete. A tire marked C
may have poor traction performance.
6-81

{WARNING:
Wheel nuts that are improperly or incorrectly
tightened can cause the wheels to become loose or
come off. The wheel nuts should be tightened with
a torque wrench to the proper torque specification
after replacing. Follow the torque specification
supplied by the aftermarket manufacturer when
using accessory locking wheel nuts. SeeCapacities
and Specications on page 6-116for original
equipment wheel nut torque specifications.
Notice:Improperly tightened wheel nuts can lead
to brake pulsation and rotor damage. To avoid
expensive brake repairs, evenly tighten the wheel
nuts in the proper sequence and to the proper
torque specication. SeeCapacities and
Specifications on page 6-116for the wheel nut
torque specication.11. Use the wheel wrench to tighten the nuts firmly.
Turn the wheel wrench clockwise and in a
crisscross sequence as shown.
12. Put the wheel cover or the center cap and plastic
wheel nut caps back on. Remove any wheel blocks.
Have a technician check the wheel nut tightness
of all wheels with a torque wrench after the first
100 miles (160 km) and then 1,000 miles (1600 km)
after that. Repeat this service whenever you have
a tire removed or serviced. SeeCapacities and
Specications on page 6-116for more information.
6-96

Vehicle Identication
Vehicle Identication Number (VIN)
This legal identifier is in the front corner of the
instrument panel, on the driver side. It can be seen
through the windshield from outside. The VIN also
appears on the Certification/Tire and Service Parts
labels and certificates of title and registration.
Engine Identication
The eighth character in the VIN is the engine code.
This code identifies the vehicle’s engine, specifications,
and replacement parts. See “Engine Specifications”
underCapacities and Specications on page 6-116for
the vehicle’s engine code.
Service Parts Identication Label
This label, on the front passenger door frame, has the
following information:
•Vehicle Identification Number (VIN)
•Model designation
•Paint information
•Production options and special equipment
Do not remove this label from the vehicle.
Electrical System
Add-On Electrical Equipment
Notice:Do not add anything electrical to the
vehicle unless you check with your dealer/retailer
rst. Some electrical equipment can damage
the vehicle and the damage would not be covered
by the vehicle’s warranty. Some add-on electrical
equipment can keep other components from
working as they should.
Add-on equipment can drain the vehicle battery, even if
the vehicle is not operating.
6-109

Maintenance Schedule......................................7-2
Introduction...................................................7-2
Scheduled Maintenance...................................7-3
Owner Checks and Services..........................7-10Recommended Fluids and Lubricants...............7-12
Maintenance Replacement Parts.....................7-14
Engine Drive Belt Routing..............................7-15
Maintenance Record.....................................7-16
Section 7 Maintenance Schedule
7-1

Maintenance Schedule
Introduction
This maintenance section applies to vehicles with a
gasoline engine. For diesel engine vehicles, see
the maintenance schedule section in the DURAMAX
Diesel manual.
Notice:Maintenance intervals, checks, inspections,
recommended uids, and lubricants are necessary
to keep this vehicle in good working condition.
Damage caused by failure to follow scheduled
maintenance might not be covered by the vehicle
warranty.
Proper vehicle maintenance helps to keep the vehicle in
good working condition, improves fuel economy, and
reduces vehicle emissions for better air quality.
Because of all the different ways people use vehicles,
maintenance needs vary. The vehicle might need
more frequent checks and services. Please read the
information under Scheduled Maintenance. To keep the
vehicle in good condition, see your dealer/retailer.The maintenance schedule is for vehicles that:
•carry passengers and cargo within recommended
limits on the Tire and Loading Information label.
SeeLoading the Vehicle on page 5-19.
•are driven on reasonable road surfaces within legal
driving limits.
•use the recommended fuel. SeeGasoline Octane
on page 6-6.
{WARNING:
Performing maintenance work on a vehicle can be
dangerous. In trying to do some jobs, you can be
seriously injured. Do your own maintenance work
only if you have the required know-how and the
proper tools and equipment for the job. If you have
any doubt, see your dealer/retailer to have a
qualified technician do the work. SeeDoing Your
Own Service Work on page 6-4.
7-2