GMC SIERRA 1995 Owners Manual

Rear Lamps - Pickup Models
1. Open the tailgate.
2. Remove the two
rear lamp
assembly screws
near the tailgate
latch and pull out
the lamp assembly.
3. Remove the
screws from the
bulb retainer and
take it
off the
lamp assembly.
4. Pull the old bulb
straight out
of the
socket.
5. Put in a new bulb
and push it in
until it is tight.
6. Replace the bulb
retainer.
7. Replace the rear lamp assembly and tighten the screws.
8. Close the tailgate.
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Rear Lamps - Chassis Cab Models
d
1. Using your
hands, peel the
rubber seal away
from the lens.
2. Lift the lens off
the lamp
assembly.
3. Slide the socket
out
of the lamp
assembly.
4. Push in gently on
the bulb, turn it to
the left and remove
it from
the socket.
5. Put in a new bulb
and, pushing
in
gently, turn it to
the right
until it is
tight.
6. Put the socket back in the lamp assembly and replace the lens and lens
seal.
Exhaust System
To help prevent damage to your exhaust system, do not continue to drive
your vehicle
if you notice:
0 Engine misfiring
0 Loss of performance
0 Exhaust system components hanging lower than normal
0 Loud exhaust system noises
0 Other unusual operating conditions
Have
your engine and exhaust system serviced regularly.
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Three- Way Catalytic Converter (Gasoline Engines)
Your vehicle’s three-way catalytic converter is designed to reduce the
pollutants
in your vehicle‘s exhaust. Use only unleaded fuel in your vehicle.
If you use leaded fuel, you could damage your three-way catalytic converter
and other engine components.
Oxidation Catalytic Converter (Diesel Engines)
Your vehicle’s oxidation catalytic converter is designed to reduce the
particulates
in your vehicle‘s exhaust. If your vehicle’s oxidation catalytic
converter ever needs to be replaced,
it must be replaced with an oxidation
converter intended for use
with diesel engines only.
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) G VWR
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.
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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.
A CAUTION:
Poorly maintained and improperly used tires are dangerous.
Overloading your tires can cause overheating as a result of too
much friction. You could have an air-out and a serious
accident. See “Loading Your Vehicle” in the Index.
Underinflated tires pose the same danger as overloaded tires.
The resulting accident could cause serious injury. Check all
tires frequently to maintain the recommended pressure. Tire
pressure should be checked when your tires are cold.
Overinflated tires are more likely to be cut, punctured, or
broken by
a sudden impact, such as when you hit a pothole.
Keep tires
at the recommended pressure.
Worn, old tires can cause accidents. If your tread is badly
worn, or if your tires have been damaged, replace them.
Inflation - Tire Pressure
The Certification/Tire 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“ tneans 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:
0 Too much flexing
Too much heat
0 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.
If your vehicle has dual rear
wheels, also see
“Dual Tire Operation” later in this section.
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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
I
II
FRT
If your vehicle has single rear wheels, always use one of the correct rotation
patterns shown here when rotating your tires.
If your vehicle has front tires with different load ranges
or tread designs
(such as all season vs. on/off road) than the rear tires. don‘t rotate your tires
front
to rear.
W v
If your vehicle has dual rear wheels and the load range and tread design for
your front tires
is the same as your rear tires, always use one of the correct
rotation patterns shown here when rotating your tires.
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If your vehicle has dual rear wheels and the load range or tread design for
your front tires is different from your rear tires, always use the correct
rotation pattern shown here when rotating your tires. The dual tires are
rotated as a pair, and the inside rear tires become the outside rear tires.
When you install dual wheels, be sure the vent holes in the inner and outer
wheels
on each side are lined up.
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.
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When it’s Time for New Tires
You need a new tire if:
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.
0 You can see the indicators at three or more places around the tire.
0 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 repaired well
because
of the size or location of the damage.
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.
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A CAUTION:
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.
Buying New Tires
To find out what kind and size of tires you need, look at the
CertificationRire label.
The tires installed on your vehicle when
it was new 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.
I A CAUTION:
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.
Be sure to use the same size and type tires on all four 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.)
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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. 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 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 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, 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.
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