tire pressure CHEVROLET EXPRESS 2007 Owner's Manual

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 Ination Pressure
:Vehicle
manufacturer’s recommended tire inflation
pressure as shown on the tire placard.
SeeInation - Tire Pressure on page 6-68
andLoading the Vehicle on page 5-19.
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. SeeWhen It Is Time for New Tires
on page 6-78.
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 6-81.
Vehicle Capacity Weight
:The number of
designated seating positions multiplied by 150 lbs
(68 kg) plus the rated cargo load. SeeLoading
the Vehicle on page 5-19.
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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
inflation pressure. See “Tire and Loading
Information Label” underLoading the Vehicle
on page 5-19.
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 vehicle specific Tire and Loading Information
label is attached to your vehicle. This label shows
your vehicle’s original equipment tires and the
correct inflation pressures for your tires when they
are cold. The recommended cold tire inflation
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, seeLoading
the Vehicle on page 5-19. How you load your
vehicle affects vehicle handling and ride comfort.
Never load your vehicle with more weight than it
was designed to carry.
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When to Check
Check your tires once a month or more.
Do not forget to check the pressure of the spare
tire. SeeSpare Tire on page 6-101for additional
information.
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
underinflated. 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
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.
Recheck 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.
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Dual Tire Operation
When the vehicle is new, or whenever a wheel, wheel bolt
or wheel nut is replaced, check the wheel nut torque after
100, 1,000 and 6,000 miles (160, 1 600 and 10 000 km)
of driving. For proper wheel nut tightening information,
see “Removing the Flat Tire and Installing the Spare
Tire” later in this section, underChanging a Flat Tire
on page 6-86. Also see “Wheel Nut Torque” under
Capacities and Specications on page 6-116.
The outer tire on a dual wheel setup generally wears
faster than the inner tire. Your tires will wear more
evenly and last longer if you rotate the tires periodically.
SeeTire Inspection and Rotation on page 6-75. Also
seeScheduled Maintenance on page 7-3.
{WARNING:
If you operate your vehicle with a tire that is badly
underinflated, the tire can overheat. An overheated
tire can lose air suddenly or catch fire. You or
others could be injured. Be sure all tires (including
the spare) are properly inflated.
SeeTires on page 6-60andInation - Tire Pressure on
page 6-68for more information on proper tire inflation.
Tire Pressure Monitor System
The Tire Pressure Monitor System (TPMS) uses radio
and sensor technology to check tire pressure levels.
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.)
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.
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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.
SeeTire Pressure Monitor Operation on page 6-72for
additional information.
Federal Communications
Commission (FCC) and Industry
and Science Canada
SeeRadio Frequency Statement on page 8-20
for information regarding Part 15 of the Federal
Communications Commission (FCC) Rules and
RSS-210/211 of Industry and Science Canada.
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Tire Pressure Monitor Operation
This vehicle may have a Tire Pressure Monitor
System (TPMS). The TPMS is designed to warn the
driver when a low tire pressure condition exists. TPMS
sensors are mounted onto each tire and wheel assembly,
excluding the spare tire and wheel assembly. The TPMS
sensors monitor the air pressure in the vehicle’s tires and
transmits the tire pressure readings to a receiver located
in the vehicle.
When a low tire pressure
condition is detected, the
TPMS will illuminate the
low tire pressure warning
symbol located on the
instrument panel cluster.
At the same time a message to check the pressure in a
specific tire appears on the Driver Information Center
(DIC) display. The low tire pressure warning light and the
DIC warning message come on at each ignition cycle
until the tires are inflated to the correct inflation pressure.If your vehicle has DIC buttons, tire pressure levels can
be viewed by the driver. For additional information and
details about the DIC operation and displays seeDIC
Operation and Displays on page 4-37andDIC Warnings
and Messages on page 4-44.
The low tire pressure warning light may come on in
cool weather when the vehicle is first started, and then
turn off as you start to drive. This could be an early
indicator that the air pressure in the tire(s) are getting
low and need to be inflated to the proper pressure.
A Tire and Loading Information label, attached to
your vehicle, shows the size of your vehicle’s original
equipment tires and the correct inflation pressure for
your vehicle’s tires when they are cold. SeeLoading the
Vehicle on page 5-19, for an example of the Tire and
Loading Information label and its location on your vehicle.
Also seeInation - Tire Pressure on page 6-68.
Your vehicle’s TPMS can warn you about a low tire
pressure condition but it does not replace normal
tire maintenance. SeeTire Inspection and Rotation
on page 6-75andTires on page 6-60.
Notice:Liquid tire sealants could damage the Tire
Pressure Monitor System (TPMS) sensors. Sensor
damage caused by using a tire sealant is not
covered by your warranty. Do not use liquid tire
sealants.
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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.
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4. Start with the driver side front tire.
5. Remove the valve cap from the valve cap stem.
Activate the TPMS sensor by increasing or
decreasing the tire’s air pressure for five seconds,
or until a horn chirp sounds. The horn chirp, which
may take up to 30 seconds to sound, confirms that
the sensor identification code has been matched to
this tire and wheel position.
6. Proceed to the passenger side front tire, and repeat
the procedure in Step 5.
7. Proceed to the passenger side rear tire, and repeat
the procedure in Step 5.
8. Proceed to the driver side rear tire, and repeat the
procedure in Step 5. The horn sounds two times to
indicate the sensor identification code has been
matched to the driver side rear tire, and that the
TPMS sensor matching process is no longer active.
The TIRE LEARNING ACTIVE message on the DIC
display screen goes off.
9. Turn the ignition switch to LOCK/OFF.
10. Set all four tires to the recommended air pressure
level as indicated on the Tire and Loading
Information label.
11. Put the valve caps back on the valve stems.Tire Inspection and Rotation
Inspect tires regularly for signs of wear or damage.
Also inspect the spare tire. For more information
on tire inspection, seeWhen It Is Time for
New Tires on page 6-78.
Tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km). SeeScheduled Maintenance
on page 7-3.
The purpose of a regular tire rotation is to achieve
a uniform wear for all tires on the vehicle. This will
ensure that the vehicle continues to perform most
like it did when the tires were new. The first rotation
is the most important. SeeScheduled Maintenance
on page 7-3.
Any time you notice unusual wear, rotate the 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 6-78andWheel
Replacement on page 6-82.
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If the vehicle has dual rear wheels and the tread
design for the front tires is different from the dual
rear tires, always use the correct rotation pattern
shown here when rotating the tires. The dual tires
are rotated as a pair and the inside rear tires
become the outside rear tires.
When you install dual wheels, be sure that vent
holes in the inner and outer wheels on each
side are lined up.
Also seeDual Tire Operation on page 6-70for
additional information.
After the tires have been rotated, adjust the front
and rear inflation pressures as shown on the Tire
and Loading Information label. SeeInation - TirePressure on page 6-68andLoading the Vehicle
on page 5-19. Make certain that all wheel nuts are
properly tightened. See “Wheel Nut Torque” under
Capacities and Specications on page 6-116.
{WARNING:
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 6-86.
If your vehicle has a Tire Pressure Monitor
System (TPMS), reset the TPMS sensors after
rotating the tires. SeeTire Pressure Monitor
Operation on page 6-72.
Make sure the spare tire is stored securely. Push,
pull, and then try to rotate or turn the tire. If it
moves, tighten the cable. SeeStoring a Flat or
Spare Tire and Tools on page 6-100.
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When It Is Time for New Tires
Various factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road conditions,
influence when you need new tires.
One way to tell when it is
time for new tires is to
check the treadwear
indicators, which appear
when your tires have only
1/16 inch (1.6 mm) or less
of tread remaining.
Some commercial truck tires, including Goodyear
LT225/75R16 G949 RSA and Goodyear LT225/75R16
G933 RSD, may not have treadwear indicators. If the
tires do not have treadwear indicators, replace the tires
when the tread depth is down to 1/8 inch (3.2 mm) for
the front tires, or 1/16 inch (1.6 mm) for the rear tires.You need new tires 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.
The rubber in tires degrades over time, even if they are
not being used. This is also true for the spare tire, if your
vehicle has one. Multiple conditions affect how fast this
aging takes place, including temperatures, loading
conditions, and inflation pressure maintenance. With
proper care and maintenance tires will typically wear out
before they degrade due to age. If you are unsure about
the need to replace your tires as they get older, consult
the tire manufacturer for more information.
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