1993 GMC SIERRA tire type

Your Driving and the Road
the right lane. (Remember that your right outside mirror is c\
onvex. The
vehicle you just passed may seem to be farther away from you \
than
it
really is).
Try not to pass more than one vehicle at a time on two-lane roads.
Don’t overtake a slowly moving vehicle too rapidly. Even though the
Reconsider before passing the next vehicle.
brake lights are not flashing, it may be slowing down
or starting to turn.
If you’re being passed, make it easy for the following driver to get ahead
of you. Perhaps you can ease a little
to the right.
Loss of Control
Let’s review what driving experts say about what happens whe\
n the three
control systems (brakes, steering and acceleration) don’t ha\
ve enough friction
where the tires meet the road to do what the driver has asked.
In any emergency, don’t give up. Keep trying to steel+-, arid constantly seek an
escape route
or area of less danger.
Skidding
In a skid, a driver can lose control of the vehicle. Defensive drivers avoid
most skids by taking reasonable care suited
to existing conditions, and by not
“overdriving” those conditions. But skids are always possib\
le.
The three types
of skids correspond to your vehicle’s three control systems.
In the braking skid your wheels aren’t rolling. In the steering
or cornering
skid, too much speed
or steering in a curve causes tires to slip and lose
cornering force. And in the acceleration skid too much throttle\
causes the
driving wheels to spin.
A cornering skid and an acceleration skid are best handled by ea\
sing your
foot
off the accelerator pedal. If your vehicle starts to slide (as when you turn
a corner on a wet, snow-
or ice-covered road), ease your foot off the
accelerator pedal as soon as you feel the vehicle start to sl\
ide. Quickly steer
the way you want the vehicle
to go. If you start steering quickly enough, your
vehicle
will straighten out. As it does, straighten the front wheels.
Of course, traction is reduced when water, snow, ice, gravel, or other material
is on the road.
For safety, you’ll want to slow down and adjust your driving to
these conditions. It is important to slow down on slippery surfaces because
stopping distance will be longer and vehicle control more limit\
ed.
While driving on a surface with reduced traction,
try your best to avoid
sudden steering, acceleration,
or braking (including engine braking by shifting
to a lower gear). Any sudden changes could cause the tires to slid\
e. You
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Slow down, especially on higher speed roads. Your headlights ca\
n light
In remote areas, watch for animals.
If you’re tired, pull off the road in a safe place and rest.
up only
so much road ahead.
Night Vision
No one can see as well at night as
in the daytime. But as we get older
these differences increase.
A 50-year-old driver may require at least twice as
much light to see the same thing at night as a 20-year-old.
What you do in the daytime can also affect your night vision.\
For example, if
you spend the day in bright sunshine you are wise to wear sunglasses. Your
eyes will have less trouble adjusting to night.
But if you’re driving, don’t wear sunglasses at night. Th\
ey may cut down on
glare from headlights, but they also make a lot of things inv\
isible that should
remain visible-such as parked cars, obstacles, pedestrians, or e\
ven trains
blocking railway crossings. You may want
to put on your sunglasses after you
have pulled into a brightly-lighted service or refreshment area.\
Eyes shielded
from that glare may adjust more quickly to darkness back on t\
he road. But
be sure to remove your sunglasses before you leave the service\
area.
You can be temporarily blinded by approaching lights.
It can take a second or
two, or even several seconds, for your eyes to readjust to the dark. When
you are faced with severe glare (as from a driver who doesn’\
t lower the high
beams, or a vehicle with misaimed headlights), slow down a little. Avoid\

staring directly into the approaching lights. If there is a line of opposing
traffic, make occasional glances over the line of headlights to make certain
that one of the vehicles isn’t starting to move into your lane. Once you are
past the bright lights, give your eyes time to readjust before\
resuming speed.
High Beams
If the vehicle approaching you has its high beams on, signal by \
flicking yours
to high and then back to low beam. This is the usual signal to lower the
headlight beams.
If the other driver still doesn’t lower the beams, resist the
temptation to put your high beams on. This only makes
two half-blinded
drivers.
On a freeway, use your high beams only in remote areas where \
you won’t impair approaching drivers. In some places, like cities, using \
high beams is
illegal.
When you follow another vehicle on a freeway or highway, use \
low beams.
True, most vehicles now have day-night mirrors that enable the \
driver to
reduce glare. But outside mirrors are not
of this type and high beams from
behind can bother the driver ahead.
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Your Driving and the Road
Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inflated to the 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.
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 righ\
t hitch.
Here are some rules
to follow:
If your vehicle has a step bumper and you are going to use a ball-type
hitch, remove the pad and cut holes in
it to match the hitch and safety
chain holes in the bumper.
If you’ll be pulling a trailer that, when loaded, will weigh more than 4,000
pounds (1800 kg) 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.
Safety Chains
You should always attach chains between your vehicle and your trail\
er. Cross
the safety chains under the tongue of the trailer
so that the tongue will not
drop
to the road if it becomes separated from the hitch. Instructions about
safety chains may be provided by the hitch manufacturer
or by the trailer
manufacturer. Follow the manufacturer’s recommendation for atta\
ching safety
chains. Always leave just enough slack
so you can turn with your rig. And,
never allow safety chains to drag .on the ground.
Trailer Brakes
If your trailer weighs more than 1,000 pounds (450 kg) loaded, then it needs
its own brakes-and they must be adequate. Be sure
to read and follow the
instructions for the trailer brakes
so you’ll be able to install, adjust and
maintain them properly.
Don’t tap into your vehicle’s brake system
if the trailer’s brake system will use
more than
0.02 cubic inch (0.3~~) of fluid from your vehicles master cylinder.
If it does, both braking systems won’t work well. You could even lose your
brakes.
Will the trailer brake parts take 3,000 psi (20 650 kPa) of pressure? If
not, the trailer brake system must not be used with your vehi\
cle.
If everything checks out this far, then make the brake fluid tap at the
port on the master cylinder that sends fluid
to the rear brakes. But don’t
use copper tubing for this.
If you do, it will bend and finally break off.
Use steel brake tubing.
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Service & Appearance Care
When to Check: Check your tires once a month or more. Also, check the
tire pressure of the spare tire.
How to Check: Use a good quality pocket-type gage to check tire pressure.
Simply looking at the tires will not tell you the pressure, e\
specially
if you
have radial tires-which may look properly inflated even if they\
’re
underinflated.
If your tires have valve caps, be sure to put them back on. They help
prevent leaks by keeping out dirt and moisture.
Special Tire Inflation
If you have 16 inch tires on your vehicle, and:
- You’ll be driving for very long at speeds of 66 mph (1 05 km/h) to 75
mph (120 kmlh) where legal, inflate tires 10 psi (70 kPa) more than
the recommended cold inflation pressure.
- You’ll be driving for very long at speeds of 76 mph (120 kmlh) to 85
mph (1 35 km/h) where legal, cold inflation pressure should be
increased by
10 psi (70 kPa) and you must also reduce axle load
capacity by
10%. Do not drive over 85 mph (135 kdh) even if
it’s legal.
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r CAUTION I
If you operate your vehicle with a tire that is badly underinflated, the
tire can overheat. An overheated tire can lose air suddenly or catcl.
fire. You or others could be injured. Be sure all tires (including the
spare,
if any) are properly inflated.
Buying New Tires
To find out what kind and size of tires you need, look at the Certificationflire
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 num\
ber. That
way, your vehicle will continue to have tires that are designed to give proper
endurance, handling, speed rating, traction, ride and other thin\
gs during
normal service on your vehicle. If your tires have an all-season tread design,
the TPC number will be followed by a
“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.
1 CAUTION
* Mixing tires could cause you to lose control while driving. If you mix
vehicle may not handle properly, and you could have a crash. Be
- ) tires of different sizes or types (radial and bias-belted tires), the
I sure to use the same size and type tires on all wheels. I
Uniform Tire Qua/ity Grading
The following information relates to the system developed by the United
States National Highway Traffic Safety Administration which grade\
s tires by
treadwear, traction and temperature performance. (This applies o\
nly to
vehicles sold in the United States.)
Treadwear
The treadwear grade is a comparative rating based on the wear rate of the
tire when tested under controlled conditions on a specified governmen\
t 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 var\
iations in
driving habits, service practices and differences in road characteristics and
climate.
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Service & Appearance Care
Traction-A, B, C
The traction grades, from highest to lowest are: A, B, and C. 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.
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 laborat\
ory 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, underinfla\
tion, or
excessive loading, either separately or in combination, can caus\
e heat buildup
and possible tire failure.
These grades are molded on the sidewalls of passenger car tire\
s. While the tires available as standard or optional equipment on \
General Motors
vehicles may vary with respect to these grades, all such tires meet General
Motors performance standards and have been approved for use on \
General
Motors vehicles.
All passenger type (P Metric) tires must conform to Federal
safety requirements in addition to these grades.
Wheel AIignment 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.
In
most cases, you will not need to have your wheels aligned again.
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.
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Service & Appearance Care
Tire Chains
If your vehicle has dual wheels or LT265175R16 size tires, don’t use tire
chains; they can damage your vehicle.
__ you don’t have dual wheels or if you have a tire size other than
LT265/75R16, use tire chains only when you must. Use only
SAE
“S” type chains that are the proper size for your tires. Install \
them on the
tires of the rear axle. 3
Tighten the as tightly as possible with the ends securely fastened. Drive I
slowly and TOIIOW 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 with chains on will ’
nage your vehicle.
1 CAUTION
Appearance Cam
I
Cleaning products can be hazardous. Some are toxic. Others can \
L 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
zlosed space. When you use anything in a container to clean your
vehicle, be sure
to follow the instructions. And always open your
doors or windows when you’re cleaning the inside.
I ter use these to clean your vehicle:
Gasoline
Benzene
Naphtha
Carbon Tetrachloride
Acetone
Paint Thinner
Turpentine
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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NOTICE I
I Don’t use any of these unless anual says you can. In many uses,
!v will damage your vehicle:
Reducing Agents
Cleaning the Inside of Your Vehicle
Use a vacuum cleaner often to get rid of dust and loose dirt. Wipe vinyl with
a clean, damp cloth.
Your GM dealer has two
GM cleaners-a solvent-type spot lifter and a
foam-type powdered cleaner. They will clean normal spots and st\
ains very
well.
Here are some cleaning tips:
Always read the instructions on the cleaner label.
Clean up stains as soon as you can-before they set.
Use a clean cloth or sponge, and change to a clean area often. A soft
Use solvent-type cleaners in a well ventilated area only. If you use them,
brush
may be used
if stains are stubborn.
don’t saturate the stained area.
If a ring forms after spot cleaning, clean the entire area immedi\
ately or it
will set.
Using Foam-Type Cleaner on Fabric
Vacuum and brush the area to remove any loose dirt.
Always clean a whole trim panel or section. Mask surrounding t\
rim along
stitch or welt lines.
Mix Multi-Purpose Powdered Cleaner following the directions on the
container label.
Use suds only and apply with a clean sponge.
Don’t saturate the material.
Don’t rub it roughly.
As soon as you’ve cleaned the section, use a sponge to remove the
suds.
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