tire size GMC SIERRA 1997 Owners Manual

Loading Your Vehicle
I-
GAWR FRT
RIM COLD TIRE PRESSURE
-!=2 - I
The Certificationrnire label is found on the rear edge of
the driver’s door or in the Incomplete Vehicle Document
in the cab.
The label shows the size of
your original tires and the
inflation pressures needed to obtain the gross weight
capacity
of your vehicle. This is called the GVWR
(Gross Vehicle Weight Rating). The GVWR includes the
weight
of the vehicle, all occupants, fuel and cargo.
The Certificationmire label also tells you the maximum
weights for the front and rear axles, called Gross Axle Weight Rating (GAWR). To find out the actual loads on
your front and rear axles, you need
to go to a weigh
station
and weigh your vehicle. Your dealer can help
you
with this. Be sure to spread out your load equally on
both sides of the centerline.
Never exceed the
GVWR for your vehicle, or the
GAWR for
either the front or rear axle.
And, if you do have a heavy load, you should spread
it out.
/;1 CAUTION:
In the case of a den stop or collision, things
carried in the bed of your truck could shift
forward and come into the passenger area,
injuring you and others. If you put things in the
bed
of your truck, you should make sure they are
properly secured.
Using heavier suspension components to get added
durability might not change your weight ratings. Ask
your dealer to help you load
your vehicle the right way.
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A B
If you’re using a weight-carrying hitch, the trailer
tongue
(A) should weigh 10 percent of the total loaded
trailer weight
(B). If you’re using a weight-distributing
hitch, the trailer tongue
(A) should weigh 12 percent of
the total loaded trailer weight (B).
After you’ve loaded your trailer, weigh the trailer and
then
the tongue, separately, to see if the weights are
proper. If they aren’t,
you may be able to get them right
simply by moving some items around
in the trailer.
Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inflated to the upper
limit for cold tires. You’ll find these numbers on the
Certification label at the rear edge
of the driver’s door or
see “Tire Loading”
in the Index. Then be sure you don’t
go over the GVW limit for your vehicle, including the
weight of the trailer tongue.
Hitches
It’s important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads are a
few reasons why
you’ll need the right hitch. Here are
some rules to follow:
0 If you use a step-bumper hitch, your bumper could
be damaged in sharp turns. Make sure
you have
ample room when turning
to avoid contact between
the trailer and the bumper.
0 If you’ll be pulling a trailer that, when loaded, will
weigh more than
the capacity stamped on your step
bumper, be sure
to use a properly mounted,
weight-distributing hitch and sway control of the
proper size. This equipment
is very important for
proper vehicle loading and good handling when
you’re driving.
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When It’s Time for New Tires
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.)
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
around the tire.
0 You can see cord or fabric showing through the
0 The tread or sidewall is cracked, cut or snagged deep
tire’s rubber.
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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Dual Tire Operation Buying New Tires
To find
out what kind and size of tires you need, look
at the CertificationEire label. When the vehicle is new, or whenever a wheel, wheel bolt
or wheel
nut is replaced, check the wheel nut torque after
100,
1,OOO and 6,000 miles (160, 1 600 and 10 OOO 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.
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,
if any) are properly inflated.
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.
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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.
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.
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I 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.
I 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.
Whenever a wheel, wheel bolt or wheel
nut is replaced
on a dual wheel setup, 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. See
“Changing a
Flat Tire” in the Index for
more information.
Used Replacement Wheels
~
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 an
new
GM original equipment wheel.
~ accident. If you have to replace a wheel, use a
Tire Chains
I NOTICE:
If your vehicle has dual wheels or P26975R16 size
tires, don’t use tire chains. They can damage
your
vehicle because there’s not enough clearance.
NOTICE: (Continued)
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NOTICE: (Continued)
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.
If you do find traction devices that will fit, install
them on the rear tires.
If you don’t have dual wheels or if you have a
tire size other than
P265175R16, 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.
Don’t use chains on the tires of the front 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
Benzene
Naphtha
0 Carbon Tetrachloride
0 Acetone
0 Paint Thinner
Turpentine
Lacquer Thinner
0 Nail Polish Remover
They can all be hazardous
-- some more than
others
-- and they can all damage your vehicle, too.
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