
Downloaded from www.Manualslib.com manuals search engine After the tires have been rotated, adjust the front and rear
inflation pressures as shown on the Certificatioflire label.
Make certain that
all wheel nuts are properly tightened.
See “Wheel Nut Torque” in the Index.
1
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.
Some commercial truck
tires may not have
treadwear indicators.
You need
a new tire if any of the following statements
are true:
0 You can see the indicators at three or more places
0 You can see cord or fabric showing through the
around the tire.
tire’s rubber.
0 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 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 torque, see “Wheel
Nut Torque’’ in
the Index.
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.
If you’re going to be doing a lot
of driving on
high-crown roads, you can reduce tire wear by adding
5 psi (35 kPa) to the tire pressure in the outer tires. Be
sure
to return to the recommended pressures when no
longer driving under those conditions. See “Changing a
Flat Tire” in the Index for more information.
A CAUTION:
Buying New Tires
To find out what kind and size of tires you need, look at
the Certificationrnire 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.
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.

Downloaded from www.Manualslib.com manuals search engine Mixing tires could cause you to lose control 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.
1
Uniform Tire Quality Grading
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.
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 -- 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 (straightahead) traction tests and does not
include cornering (turning) traction.

Downloaded from www.Manualslib.com manuals search engine Tire Chains
NOTICE:
Use tire chains only where legal and only when
you must. Use chains that are the proper size
for your tires. Install them on the tires of the
rear axle.
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.
Appearance Care
Remember, cleaning products can be hazardous. Some
are toxic. Others can burst
into flame if you strike a
match or get them on a hot part of the vehicle. Some are
dangerous if you breathe their fumes in a closed space.
When you use anything from a container to clean your
vehicle, be sure to follow the manufacturer’s warnings
and instructions. And always open your doors or
windows when you’re cleaning the inside.
Never use these to clean your vehicle:
Gasoline
0 Benzene
0 Naphtha
Carbon Tetrachloride
Acetone
Paint Thinner
Turpentine
0 Lacquer Thinner
Nail Polish Remover
They can all be hazardous
-- some more than
others
-- and they can all damage your vehicle, too.
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