tires GMC SIERRA 1993 Owner's Guide

- Inflation pressures should never exceed 10 psi (70 kPa) above the
inflation specified for the maximum load of the tire.
If you have 19.5 inch radial tires on your vehicle, and:
- You’ll be driving for very long at speeds of 66 mph (105 km/h) to 70
mph (110 km/h) where legal, inflate tires- to 5 psi (35 kPa) more than
the recommended cold inflation pressures and reduce axle load
capacity by 4%.
- You’ll be driving for very long at speeds of 71 mph (1 15 km/h) to 75
mph (120 kmlh) where legal, cold inflation pressures should be
increased by
5 psi (35 kPa) and you must also reduce axle load
capacity by
12% Do not drive over 75 mph (120 kmh) even if it’s
legal.
inflation specified for the maximum load of the tire.
- Inflation pressures should never exceed 20 psi (140 kPa) above the
For special operating conditions, such as carrying a slide-in c\
amper,
increase recommended cold tire pressures
by 10 psi (70 kPa).
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Service & Appearance Cam
Tire lnspecfion and Rotation
To make your tires last longer, have them inspected and rotated at the
mileages recommended in the Maintenance Schedule. See “Scheduled
Maintenance Services” in the Index.
Q
-
-
K2655
Use this rotation pattern.
If your vehicle has front tires with different load ratings or tread designs (such
as all season
vs. onloff road) than the rear tires, don’t rotate your tires \
front
to rear.
After the tires have been rotated, adjust the front and rear \
inflation pressure
as shown on the CertificationRire label. Make certain that all wheel nuts are
properly tightened. See “Wheel Nut Torque”
in the Index.
A Rust or dirt on a wheel, or on the parts to which -it is fastened, can
make the wheel nuts become loose after a time. The wh.eel 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 paper towel to do this; but
3 be sure to use a scraper or wire brush later, if you need- to, to get
-T all the rust or dirf off. See “Changing a Flat Tire” in the Index.
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Dual Tire Rotation
K2659
Use one of these patterns if you have the same tire sizes and load ranges
on the front and rear.
K2660
1
Use this pattern if your front and rear tires are different sizes or load ranges.
When you install dual wheels, be sure the vent holes in the wheels are
lined up.
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Service & Appearance Cam
When It’s Time for New Tires
K1656
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
2/32 inch (1.6 mm) or
less of tread remaining.
You need a new tire
if:
You can see the indicators at three places around the tire.
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.
The tire has a bump, bulge or split.
The tire has a puncture, cut, or other damage that can’t be repalred well
because of the size or location of the damage.
Dual Tire Operation
If your vehicle has dual rear wheels, the outer tire will usually\
wear 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.
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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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Wheel Replacement
Re'place any' wheel that is bent, cracked or badly rusted. If wheel nuts keep
coming loose, the wheel, wheel bolts, and wheel nuts should be\
replaced.
If
the wheel leaks air out,, replace it (except some aluminum wheels, which can
sometimes be repaired). See your GM dealer
if any of these conditions
exists. Your dealer will know what kind of wheel you need.
Each new wheel should' have the same load carrying capacity, d\
iameter,
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 equipm-ent parts. This way, you will
be sure to have the right ,wheel, wheel bolts, .and wheel nuts for your vehicle.
1 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 an collision in which you or others could be
injured. Always use the correct wheel, wheel bolts, and wheel \
nuts
for redacement.
I
NnTICF
I
Used Replacement Wheels
* Putting a used wheel on your vehicle is dangerous. You can't know
1 how it's been used or how many miles it's been driven. It could fail
suddenly and cause an accident.
If you have to replace a wheel, use
I a new GM original equipment wheel.
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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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r Machine compounding or aggressive polishing on a basecoatlclearcoat
paint finish may
dull the finish or leave swirl marks.
Protecting Exterior Bright Metal Parts
Bright metal parts should be cleaned regularly to keep their luster. Washing
with water is all that is usually needed. However, you may use GM Chrome.
Polish on chrome or stainless steel trim,
if necessary.
Use special care with aluminum trim.
To avoid damaging protective trim, never
use auto or chrome polish, steam or caustic soap to clean aluminum.
A
coating of wax, rubbed to a high polish, is recommended for all bright metal
parts.
Aluminum Wheels (If So Equipped)
Your aluminum wheels have a protective coating similar to the painted surface
of your vehicle. Don’t use strong soaps, chemicals, chrome polish,
or other
abrasive cleaners on them because you could damage this coating. After
rinsing thoroughly, a wax may be applied.
1 NOTICE
If you have aluminum wheels, don’t use an automatic vehicle wash that
has hard silicon carbide cleaning brushes. These brushes can take
off the
I protective coating.
White Side wall Tires
Your General Motors dealer has a GM White Sidewall Tire Cleaner. You can
use a stiff brush with it.
Weatherstrips
These are places where glass or metal meets rubber. Silicone g\
rease there
will make them last longer, seal better, and not stick
or squeak. Apply silicone
grease with a clean cloth at least every six months.
Sheet Metal Damage
If your vehicle is damaged and requires sheet metal repair or replacement,
make sure the body repair shop applies anti-corrosion material \
to the parts repaired or replaced to restore corrosion protection.
Foreign Material
Calcium chloride and other salts, ice melting agents, road oil and tar, tree
sap, bird droppings, chemicals from industrial chimneys, and other foreign \
matter can damage your vehicle’s finish
if they remain on painted surfaces.
Use cleaners that are marked safe for painted surfaces for these stains.
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Appearance Care Materials
PART
NUMBER SIZE
1050172 16 oz.
(0.473L)
1050173 16
oz.
(0.473L)
1050174
16 oz.
(0.473L)
1050214 32
oz.
I050729 8 oz.
(0.237L)
1051055 16
oz.
(0.473L)
1051398
8 oz.
(0.237L)
1052870 16
oz.
DESCRIPTION
Tire Cleaner Cleans white and black tires White Sidewall chrome and stainless steel and Polish Removes rust and corrosion on Chrome Cleaner
and road oil Oil Remover
Removes old waxes, polishes, tar
Tar and
Road
USAGE
VinyVLeather Spot and stain removal on leather
Cleaner or vinyl
Fabric Cleaner Spot and stain removal
on cloth
Glass Cleaner Glass cleaning and spot cleaning
Multi-Purpose Cleans vinyl and cloth on door trim,
Powder Cleaner seats, and carpet-also tires and mats
Vinyl Top Cleaning
of vinyl tops
Cleaner
Preservatone Vinyl
top dressing
Spot Lifter Spot and stain removal on cloth
Wash-Wax Exterior wash
and fabric
on vinyls
and fabric
Magic Mirror polish
Cleaner-Polish Exterior cleaner and
TO077
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