CHEVROLET EPICA 2004 1.G Owners Manual

Uniform Tire Quality Grading
Quality grades can be found where applicable on the
tire sidewall between tread shoulder and maximum
selection width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system developed
by the Unites 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.
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
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 — 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. 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.
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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.
5-58

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.
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 vehicle.{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.
SeeChanging a Flat Tire on page 5-62for more
information.
5-59

Used Replacement Wheels
{CAUTION:
Putting 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 a crash. If you have to replace a
wheel, use a new GM original equipment wheel.
Tire Chains
Notice: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 front 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.
5-60

If a Tire Goes Flat
It’s unusual for a tire to “blowout” while you’re driving,
especially if you maintain your tires properly. If air goes
out of a tire, it’s much more likely to leak out slowly.
But if you should ever have a “blowout,” here are a few
tips about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake
to a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like
a skid and may require the same correction you’d use in
a skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop, well off the road if possible.{CAUTION:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without
the appropriate safety equipment and training.
The jack provided with your vehicle is designed
only for changing a at tire. If it is used for
anything else, you or others could be badly
injured or killed if the vehicle slips off the jack.
Use the jack provided with your vehicle only for
changing a at tire.
If a tire goes flat, the next part shows how to use your
jacking equipment to change a flat tire safely.
5-61

Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your
hazard warning flashers.
{CAUTION:
Changing a tire can be dangerous. The vehicle
can slip off the jack and roll over or fall on you
or other people. You and they could be badly
injured or even killed. Find a level place to
change your tire. To help prevent the vehicle
from moving:
1. Set the parking brake rmly.
2. Put the shift lever in PARK (P).
CAUTION: (Continued)
CAUTION: (Continued)
3. Turn off the engine and do not restart
while the vehicle is raised.
4. Do not allow passengers to remain in
the vehicle.
To be even more certain the vehicle won’t
move, you should put blocks at the front and
rear of the tire farthest away from the one
being changed. That would be the tire, on the
other side, at the opposite end of the vehicle.
5-62

The following steps will tell you how to use the jack
and change a tire.
Removing the Spare Tire and Tools
The spare tire and tools you will need are located in
the trunk.
A. Jack
B. Wheel WrenchC. Jack Handle
D. Screwdriver1. Lift and remove the trim cover.
2. Turn the retainer
on the spare tire
counterclockwise
and remove the
retainer.
3. Remove the spare tire. SeeSpare Tire on page 5-68
for more information.
4. Remove the jack, the jack handle and the wheel
wrench. Your vehicle’s jack is stored in a foam
tray in the left side of the trunk. The tools are stored
in a bag in the trunk.
5-63

Removing the Flat Tire and Installing
the Spare Tire
1. If your vehicle has wheel covers, use the jack handle
to begin loosening the wheel covers. Using the flat
end of the jack handle or the screwdriver, pry along
the edge of the wheel cover until it comes off.
2. Then use the wheel wrench to loosen all the wheel
nuts. Do not remove them yet.3. Near each wheel is a notch in the frame which the
jack head fits in.
Position the jack and raise the jack head until it fits
firmly into the notch in the vehicle’s frame nearest
the flat tire. Put the spare tire near you.
5-64

{CAUTION:
Getting under a vehicle when it is jacked up is
dangerous. If the vehicle slips off the jack you
could be badly injured or killed. Never get under
a vehicle when it is supported only by a jack.
{CAUTION:
Raising your vehicle with the jack improperly
positioned can damage the vehicle and even
make the vehicle fall. To help avoid personal
injury and vehicle damage, be sure to t the
jack lift head into the proper location before
raising the vehicle.4. Insert the jack handle into the jack and the wheel
wrench onto the end of the jack handle.
5. Raise the vehicle by turning the wheel wrench
clockwise. Raise the vehicle far enough off the
ground so there is enough room for the spare tire
to fit underneath the wheel well.
6. Remove all of the wheel nuts by turning them
counterclockwise.
7. Remove the flat tire.
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8. Remove any rust or dirt
from the wheel bolts,
mounting surfaces
and spare wheel.
{CAUTION:
Rust or dirt on the wheel, or on the parts to
which it is fastened, can make the 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
the 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.
{CAUTION:
Never use oil or grease on studs or nuts.
If you do, the nuts might come loose. Your
wheel could fall off, causing a serious
accident.
9. Place the spare tire on the wheel-mounting surface.
10. Install the wheel nuts with the rounded end of the
nuts toward the wheel. Tighten each nut by hand
clockwise until the wheel is held against the hub.
11. Lower the vehicle by turning the wheel wrench
counterclockwise. Lower the jack completely.
12. Tighten the wheel nuts
firmly in a crisscross
sequence, as shown.
5-66