CHEVROLET SUBURBAN 1995 Owners Manual

Engine Control Module System
Gasoline Engines
This system has an oxygen sensor (OS) that helps keep your engine’s
air-fuel mixture at a proper
level. Use only unleaded fuel in your vehicle. If
you use leaded fuel, you could damage your oxygen sensor (OS) and
three-way catalytic converter.
Diesel Vehicles Below 8,500 (3 850 Kg) GVWR
This system monitors engine speed and throttle position. It adjusts exhaust
gas recirculation to limit emissions.
Malfunction Indicator (SERVICE ENGINE SOON)
Light
The Malfunction Indicator (SERVICE ENGINE SOON) Light on your
instrument panel lets you know when your emission system needs service.
The light will come on briefly
when you start your engine to let you know
that the system is working.
If it does not come on when you start your
engine, or if
it comes on and stays on while you’re driving, your system
may need service. Your vehicle should still be driveable, but
you should
have your system serviced right away.
Secondary Air Injection Reaction (AIR) System
(Gasoline Engines)
You may have this system. It has a control valve that will direct air to where
it is needed. If the AIR system needs service, your Malfunction Indicator
(SERVICE ENGINE
SOON) Lamp on your instrument panel will come on.
Tires
We don’t make tires. Your new vehicle comes with high-quality tires made
by
a leading tire manufacturer. These tires are warranted by the tire
manufacturers, and their warranties are delivered with every new vehicle.
If
your spare tire is a different brand than your road tires, you will have a tire
warranty folder from each
of these manufacturers.
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Inflation - lire Pressure
The CertificationD’ire label which is on the rear edge of the driver’s door, or
on the incomplete vehicle document in the cab, shows the correct inflation
pressures for your tires, when they’re cold. “Cold” means your vehicle has
been sitting for at least three hours or driven no more than a mile.
You can operate some vehicles at reduced inflation pressures
only when
you’ll be carrying reduced loads. On those vehicles, the minimum cold
inflation pressures for a typical reduced load are printed on the “Improved
Ride Tire Pressure” label located on
the driver’s door. Weigh the vehicle to
find the load on each tire and see the label for the minimum cold inflation
pressures for that load.
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NOTICE:
Don’t let anyone tell you that underinflation or overinflation is
all right. It’s not.
If your tires don’t have enough air
(underinflation) you can get:
Too much flexing
0 Too much heat
Tire overloading
Bad wear
Bad handling
0 Bad fuel economy.
If your tires have too much air (overinflation), you can get:
Unusual wear
Bad handling
Rough ride
Needless damage from road hazards.
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, especially 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.
Tire Inspection and Rotation
Tires should be inspected every 6,000 to 8,000 miles (10 000 to 13 000 km)
for any signs
of unusual wear. If unusual wear is present, rotate your tires as
soon as possible and check wheel alignment. Also check for damaged tires
or wheels. See “When it’s Time for New Tires’’ and “Wheel Replacement”
later
in this section for more information.
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The purpose of regular rotation is to achieve more uniform wear for all tires
on the vehicle. The first rotation
is the most important. See “Scheduled
Maintenance Services”
in the Index for scheduled rotation intervals.
FRT FRT
When rotating your
tires, always use the
correct rotation
pattern shown here.
When rotating your
tires,
always use one
of the correct rotation
patterns shown here.
After the tires have been rotated, adjust the front and rear inflation pressures
as shown
on the CertificatiodTire label. Make certain that all wheel nuts are
properly tightened.
See “Wheel Nut Torque” in the Index.
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When it’s Time for New Tires
Tread Wear
Indicators
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.
You need a new tire if
0 You can see the indicators at three or more places around the tire.
e You can see cord or fidbric showing through the tire’s rubber.
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.
Buying New Tires
To find out what kind and size of tires you need, look at the
Certification/Tire 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.
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Uniform lire Qualify 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.)
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
(I 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. 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, 6, 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 fdilure. 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.
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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.
These grades are molded on the sidewalls of passenger car tires.
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 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.
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.
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 GM 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.
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I NOTICE:
The wrong wheel can also cause problems with bearing life,
brake cooling, speedometer/odometer calibration, headlamp
aim, bumper height, vehicle ground clearance, and tire
or tire
chain clearance
to the body and chassis.
Used Replacement Wheels
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Tire Chains
NOTICE:
If your vehicle has LT265/75R16 size tires, don't use tire chains;
they can damage your vehicle.
If you have
a tire size other than LT26975R16, 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 manufxturer's warnings and instructions. And always open your
doors or windows when you're cleaning
the inside.
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Never use these to clean your vehicle:
0 Gasoline
Benzene
Naphtha
0 Carbon Tetrachloride
Acetone
Paint Thinner
Turpentine
0 Lacquer Thinner
0 Nail Polish Remover
They can all be hazardous
- some more than others - and they can all
damage your vehicle, too.
Don’t use any of these unless this manual says you can.
In many uses, these
will damage your vehicle:
Alcohol
Laundry Soap
Bleach
Reducing Agents
Cleaning the Inside of Your Vehicle
Use a vacuum cleaner often to get rid of dust and loose dirt. Wipe vinyl or
leather 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 stains very
well.
Do not use them on vinyl or leather.
Here are some cleaning tips:
0 Always read the instructions on the cleaner label.
0 Clean up stains as soon as you can - before they set.
0 Use a clean cloth or sponge, and change to a clean area often. A soft
brush may be used if stains are stubborn.
Use solvent-type cleaners in a well-ventilated area only. If you use
them, don’t saturate the stained area.
0 If a ring forms after spot cleaning, clean the entire area immediately or
it will set.
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