1998 CHEVROLET ASTRO Owners Manual

Downloaded from www.Manualslib.com manuals search engine A CAUTION:
Poorly maintained and improperly used tires
are dangerous.
Overloading your tires can cause
overheating as a result of too much friction.
You could have an air-out and a serious
accident. See “Loading Your Vehicle” in
the Index.
0 Underinflated tires pose the same danger as
overloaded tires. The resulting accident
could cause serious injury. Check all tires
frequently to maintain the recommended pressure. Tire pressure should be checked
when your tires are cold.
Overinflated tires are more likely to be cut,
punctured or broken by a sudden
impact
-- such as when you hit a pothole.
Keep tires
at the recommended pressure.
Worn, old tires can cause accidents. If your
tread
is badly worn, or if your tires have
been damaged, replace them.
Inflation -- Tire Pressure
The CertificatiodTire label, which is on the rear edge of
the driver’s door, shows the correct inflation pressures
for your tires when they’re cold. “Cold” means your
vehicle has been sitting for at least three hours or driven
no more than
1 mile (1.6 km).
NOTICE:
I
Don’t let anyone tell you that underinflation or
overinflation is all right. It’s not.
If your tires
don’t have enough air (underinflation), you can
get the following:
0 Too much flexing
0 Too much heat
0 Tire overloading
0 Bad wear
Bad handling
Bad fuel economy.
I
NOTICE: (Continued)
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Downloaded from www.Manualslib.com manuals search engine NOTICE: (Continued)
If your tires have too
much air (overinflation),
you can get the following:
0 Unusual wear
Bad handling
Rough ride
Needless damage from road hazards.
When to Check
Check your tires once a month or more.
Don’t forget your compact spare tire. It should be at
60 psi (420 kPa).
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell
if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they’re underinflated.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping
out dirt
and moisture.
Tire Inspection and Rotation
Tires should be rotated every 6,000 to 8,000 miles
( 10 000 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.
See “When It’s Time for New Tires” and
“Wheel Replacement’’ later in this section for
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. See “Scheduled
Maintenance Services” in
the Index for scheduled
rotation intervals.
3
When rotating your tires, always use the correct rotation
pattern shown here.
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Downloaded from www.Manualslib.com manuals search engine I
Don’t include the compact spare tire in your
tire rotation.
After the tires have been rotated, adjust the front and
rear inflation pressures as shown on the
Certificationire label. Make certain that all wheel nuts
are properly tightened. See “Wheel Nut Torque” in
the Index.
Rust or dirt on a wheel, or on the parts to which
it
is fastened, can make wheel nuts become loose
after
a 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 you
need to, to get all the rust or dirt
off. (See
“Changing
a Flat Tire” in the Index.) When
It’s Time for New Tires
One way to tell when it’s
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:
0 You can see the indicators at three or more places
around the tire.
0 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.
0 The tire has a bump, bulge or split.
0 The tire has a puncture, cut or other damage that
can’t be repaired well because of the size or location
of the damage.
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Downloaded from www.Manualslib.com manuals search engine Buying New Tires
To find out what kind and size of tires you need, look at
the CertificationRire label.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specification (TPC Spec)
number on each tire’s sidewall. When you get new tires,
get ones with that same
TPC Spec number. That way
your vehicle will continue
to have tires that are designed
to give proper endurance, handling, speed rating,
traction, ride and other things during normal service on
your vehicle.
If your tires have an all-season tread
design, the TPC number will be followed by an
“MS”
(for mud and snow).
If you ever replace your tires with those not having a
TPC Spec number, make sure
they are the same size,
load range, speed rating and construction type (bias,
bias-belted or radial) as your original tires.
I A CAUTION:
---
Mixing tires could cause you to lose contrc while
driving.
If you mix tires of different sizes or types
(radial and bias-belted tires), the vehicle may not
handle properly, and you could have
a crash.
Using tires of different sizes may also cause
damage to your vehicle. Be sure to use the same
size and type tires on all wheels.
It’s all right to drive with your compact spare,
though. It was developed for use
on your vehicle.
If you use bias-ply tires on your vehil , the
wheel rim flanges could develop cracks after
many miles of driving.
A tire and/or wheel could
fail suddenly, causing
a crash. Use only radial-ply
tires with the wheels on your vehicle.
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Downloaded from www.Manualslib.com manuals search engine Uniform Tire Quality Grading Treadwe:
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.
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 1/2) 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 -- A, B, C
The traction grades, from highest to lowest, are A, B,
and C, and they 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.
Warning: The traction grade assigned
to this tire is based
on braking (straight ahead) traction tests and does not
include cornering (turning) traction.
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Downloaded from www.Manualslib.com manuals search engine Temperature -- A, B, C
The temperature grades are A (the highest), B, and C,
representing the tire’s resistance to the generation of
heat and its ability to dissipate heat when tested under
controlled conditions on a specified indoor laboratory
test wheel. Sustained high temperature can cause the
material
of the tire to degenerate and reduce tire life, and
excessive temperature can lead to sudden tire failure.
The grade
C corresponds to a level of performance
which all passenger car tires must meet under
the
Federal Motor Vehicle Safety Standard No. 109.
Grades B and A represent higher levels of performance
on the laboratory test wheel than
the minimum required
by law.
Warning: The temperature grade for this tire is
established for a tire that is properly inflated and not
overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned and balanced
carefully
at the factory to give you the longest tire life
and best overall performance.
Scheduled wheel alignment and wheel balancing are not
needed. However,
if you notice unusual tire wear or
your vehicle pulling one
way or the other, the alignment
may need to be reset.
If you notice your vehicle
vibrating when driving on a smooth road, your wheels
may need
to be rebalanced.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted
or corroded.
If wheel nuts keep coming loose, the wheel,
wheel bolts and wheel nuts should be replaced.
If the
wheel leaks air, replace
it (except some aluminum
wheels, which can sometimes be repaired). See
your
dealer if any of these conditions exist.
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Downloaded from www.Manualslib.com manuals search engine Your dealer will know the kind of wheel you need.
Each new wheel should have
the same load-carrying
capacity, diameter,
width, offset and be mounted the
same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only
with new GM original
equipment parts. This way, you will be
sure to have the
right wheel, wheel bolts and wheel nuts for your vel
le. .
A CAUTION:
Using the wrong replacement wheels, wheel bolts
or wheel nuts on your vehicle can be dangerous.
It could affect the braking and handling of your
vehicle, make your tires lose air and make you
lose control.
You could have a collision in which
you or others could be injured. Always use the
correct wheel, wheel bolts and wheel nuts
for replacement.
NOTICE:
The wrong wheel can also cause problems with
bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper
height, vehicle ground clearance and tire or tire
chain clearance to the body and chassis.
See “Changing a Flat Tire”
in the Index for
more information.
Used R-l-ment Wh4s
rutting a used wheel on your vehicle is
dangerous, You can’t know how it’s been used or
how far it’s been driven.
It could fail suddenly
and cause an accident,
If you have to replace a
wheel, use a new
GM original equiI~ ent wheel.
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Downloaded from www.Manualslib.com manuals search engine Tire Chains
NOTICE:
If your vehicle has P235/65R15 size tires, don’t
use tire chains. They can damage your vehicle
because there’s not enough clearance.
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’s contacting your vehicle, and don’t
spin your wheels.
NOTICE: (Continued) NOTICE: (Continued)
If you do find traction devices that will fit, install
them on the rear tires.
If you have other size tires, use tire chains only
where legal and only when you must. Use only
SAE
Class “S” type chains that are the proper
size for your tires. Install them on the rear axle
tires and tighten them as tightly as possible with
the ends securely fastened, Drive slowly and
follow the chain manufacturer’s instructions,
If
you can hear the chains contacting your vehicle,
stop and retighten them.
If the contact continues,
slow down until it stops. Driving too fast or
spinning the wheels with chains on will damage
your vehicle.
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