service GMC SIERRA 1993 User Guide

.
You can only drive for a short time with the reading in either warning zone. If
you must drive, turn
off all unnecessary accessories, and have the vehicle
serviced as soon as possible.
Camper Wiring Harness
The optional 5-wire harness is stored in’ the front stake pocket on the driver’s
side of’ the bed. The harness has no connector, and should be wired by\
a
qualified electrical service person.
It must be routed out of your vehicle and
securely attached
so that it won’t be pulled or rubbed while you’re using it.
Store the -harness in its original place. Wrap the harness together and tie it
neatly
so it won3 be damaged.
The optional 7-wire harness
is stored under your vehicle along the rear frame
crossmember. The harness has a’
30 amp. in-line fused battery feed wire and
no connector, and should be wired by a qualified electrical se\
rvice person.
Securely attach
the harness to the trailer, then tape or strap it to your
vehicle’s frame rail. Be sure you leave it loose enough
so the wiring won’t
bind
or break when turning with the trailer, but not so loose that it drags on
the ground.
Store the harness in its original position. Wrap the harness together and tie it
neatly so it won’t be damaged. ,
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Comfort Contrors & Audio Systems
Care of Your Cassette Tape PIayer
A tape player that is not cleaned regularly can cause reduced so\
und quality,
ruined cassettes, or a damaged mechanism. Cassette tapes should be stored
in their cases away from contaminants, direct sunlight, and extreme\
heat.
If
they aren't, they may not operate properly or cause failure of\
the tape player.
Your tape player should be cleaned regularly each month
or after 15 hours of
use. If you notice a reduction in sound quality, try a known good cassette to
see
if the tape or the player is at fault. If this other cassette has no
improvement in sound quality, clean the tape player.
Clean your tape player with a wiping-action, non abrasive clean\
ing cassette,
and follow the directions provided with
it.
Cassettes are subject to wear and the sound quality may degrad\
e over time.
Always make sure that the cassette tape is in good condition \
before you
have your tape player serviced.
K1313
Fixed Mast Antenna
The fixed mast antenna can withstand most car washes without being
damaged.
If the mast should ever become slightly bent, you can straighten it
out by hand. If the mast is badly bent, as it might be by vandals, you should
replace
it.
Check every once in a while to be sure the mast is still tightened to the
fender.
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Your Driving and the Road
LOW
SHOULDER
WORKERS
AHEAD FLAGGER
AHEAD
I AM40200
ORANGE indicates road construction or maintenance. You’ll want to slow
down when you see an orange sign, as part of the road may be closed off
or torn up. And there may be workers and maintenance vehicles around, too.
II WES EAST
HOSPITAL
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AM402008
GREEN is used to guide the driver. Green signs may indicate upcoming
freeway exits or
show the direction you should turn to reach a particular
place.
INFORMATION
I
BLUE signs with white letters show motorists’ services.
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Your Driving and fhe Road
Brake System Warning Light
K2325
This light appears on your instrument cluster to warn you if your regular
braking’ system needs service. See “Brake System Warning L\
ight” in the
Index.
Disc Brake Wear Indicators
If you have a C 3500 HD Model, it has four-wheel disc brakes. Disc brake
pads have built-in wear indicators that make a high-pitched war\
ning sound
when the brake pads are worn and new pads are needed. The so\
und m’ay
come and go or be heard all the time your vehicle is moving (except \
when
you are pushing on the brake pedal firmly).
1 CAUTION
The brake wear warning sound means that sooner or later your
hear the brake wear warning sound, have your vehicle serviced. \
5 brakes won’t work well. That could lead to an accident. When you I ~
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brakes are first applied or lightly applied. This does not mea\
n something is
wrong with your brakes.
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may not realize the surface is slippery until your vehicle is skidding. Learn to
recognize warning clues-such as enough water, ice
or packed snow on the
road to make a “mirrored surface’’-and slow down when you have \
any
doubt.
Remember: the rear wheel anti-lock braking system (RWAL) helps\
avoid only
a rear braking skid. In a braking skid (where the front wheels are no longer
rolling), release enough pressure on the brakes to get the front wheels rolling
again. This restores steering control. Push the brake pedal dow\
n steadily
when you have to stop suddenly.
As long as the front wheels are rolling, you
will have steering control. Steer the way you want to go.
Off-Road Driving with Your FourcWheel
Drive Vehicle
This off-road guide is for vehicles that have four-wheel drive. Also, see
“Anti-lock Brakes” in the Index.
If your vehicle doesn’t have four-wheel drive,
you shouldn’t drive off-road unless you’re on a level, so\
lid surface.
Off-road driving can be great fun. But it does have some defi\
nite hazards.
The greatest
of these is the terrain itself.
“Off-roading” means you’ve left the great North American\
road system behind.
Traffic lanes aren’t marked. Curves aren’t banked. There a\
re no road signs.
Surfaces can be slippery, rough, uphill
or downhill. In short, you’ve gone right
back
to nature.
Off-road driving involves some new skills. And that’s why it’s very important
that you read this guide. You’ll find many driving tips and suggestions. These
will help make your off-road driving safer and more enjoyable. \
Before You Go Off-Roading
There are some things to do before you go out. For example, be sure to
have all necessary maintenance and service work done. Be sure \
you read all
the information about your four-wheel drive vehicle in this manual.
Is there
enough fuel?
Is the spare tire fully inflated? Are the fluid levels up where
they should be? What are the local laws that apply to off-roa\
ding where you’ll be driving?
If you don’t know, you should check with law enforcement people\

in the area. Will you be on someone’s private land?
If so, be sure to get the
necessary permission.
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Your Driving and the Road
After Off-Road Driving
Remove any brush or debris that has collected on the underbody\
, chassis, or
under the hood. These accumulations can be a fire hazard.
After operation in mud or sand, have the brake linings cleaned\
and checked. These substances can cause glazing and uneven braking. Check th\
e body
structure, steering, suspension, wheels, tires, and exhaust syste\
m for damage.
Also, check the fuel lines and cooling system for any leakage.
Your vehicle will require more frequent service due
to off-road use. Refer to
Section
7 for additional information.
Driving at Night
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Night driving is more dangerous than day driving. One reason is that some
drivers are likely
to be impaired-by alcohol or drugs, with night vision
problems, or by fatigue.
Here are some tips on night driving.
Drive defensively. Remember, this is the most dangerous time.
Don’t drink and drive (See “Drunken Driving” in the Index for more on
this problem).
Adjust your inside rear view mirror to reduce the glare from headlights
Since you can’t see as well, you may need to slow down and keep
behind
you.
more space between you and other vehicles. It’s hard
to tell how fast
the vehicle ahead is going just
by looking at its taillights.
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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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close behind you, you can allow a little extra time and flash\
your brake lights (in addition to your turn signal) as extra warning that you are about to slow
down and exit.
The exit ramp can be curvea, somerlmes quite sharply. The exit\
speed is
usually posted. Reduce your speed according to your speedometer,\
not to
your sense of motion. After driving for any distance at higher\
speeds, you
may tend to think you are going slower than you actually are.\
For example,
40 rnph (65 km/h) might seem like only 20 mph (30 km/h). Obviously, this
could lead to serious trouble
on a ramp designed for 20 mph (30 kmlh)!
Driving a Long Distance
Although most long trips today are made on freeways, there are\
still many
made on regular highways.
Long-distance driving on freeways and regular highways is the s\
ame in some
ways. The trip has to be planned and the vehicle prepared, you drive at\

higher-than-city speeds, and there are longer turns behind the \
wheel. You’ll
enjoy your trip more
if you and your vehicle are in good shape. Here are
some tips for a successful long trip.
Before Leaving on a Long Trip
Make sure you’re ready. Try to be well rested. If you must start when you’re
not fresh-such as after a day’s work-don’t plan to make too many miles
that first part of the journey. Wear comfortable clothing and \
shoes you can easily drive in.
Is your vehicle ready for a long trip? If you keep it serviced and maintained,
it’s ready to go.
If it needs service, have it done before starting out. Of
course, you’ll find experienced and able service experts in \
your vehicle’s
dealerships all across North America. They’ll be ready and willing to help \
if
you need it.
Here are some things you can check before a trip:
Windshield Washer Fluid: Is the reservoir full? Are all windows clean
Wiper Blades: Are they in good shape?
Fuel, Engine Oil, Other Fluids: Have you checked all levels?
Lights: Are they all working? Are the lenses clean?
Tires: They are vitally important to a safe, trouble-free trip. Is the tread
good enough for long distance driving? Are the tires all inflated to the
recommended pressure? inside and outside?
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‘
Your Driving and the Road
Weather Forecasts: What’s the weather outlook along your route?
Should -you delay your trip a short time to avoid a major storm system?
Maps: Do you have up-to-date maps? . .. .. . -1 .. On fhe Road
Unless you are the only driver, ‘it is good .to share the driving task’with
others. Limit turns behind the wheel to about
100 miles (160 km) or two
hours at a sitting. Then, either change drivers or stop for s\
ome- refreshment
like coffee, tea or soft drinks and some limbering up. But do\
stop and move
around. Eat lightly along the way. Heavier meals tend
to make some people
sleepy.
.. . .- , - .~
On two-lane highways or undivided multilane highways that do no\
t have
controlled access, you’ll want to watch for some situations \
not usually found
on freeways. Examples are: stop signs and signals, shopping cen\
ters with
direct access to the highway, no passing zones and school zone\
s, vehicles
turning’ left and right
off the road, pedestrians, cyclists, parked vehicles, and
even animals.
Highway Hypnosis
Is there actually such a condition as “highway hypnosis?” Or \
is it just plain ,
falling asleep at the wheel? Call it highway hypnosis, lack of awareness, or
whatever.
’ There is something about an easy stretch of road with the sam\
e scenery,
along with the hum
of the tires on the road, the drone of the engine, and the
, rush of the wind against the vehicle that can make you sleepy\
. Don’t let it ’.
happen to you! If it does, your vehicle can leave the road in less than a
second,
and you could crash and be injured.
What can you do about highway hypnosis? First, be aware that it
can
happen.
Then here are some tips:
Make sure your vehicle is well - ventilated, with a comfortably cool interior.
Keep your eyes moving. Scan the road ahead and to the sides. \
Check
your rearview mirrors frequently and your instruments from time \
to time.
This can help you avoid a fixed stare.
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,x ! - : ,-.:.&---z-.- ..* .-7
0 d
Wear good sunglasses in bright light. Glare can cause drowsiness. But
don’t wear sunglasses at night. They will drastically reduce \
your overall
-%
vision at the very time you need all the s.eeing power you h\
ave.
If you get sleepy, pull off the road into a rest, service, or parking area
and take a nap, get some exercise, or both. For safety, treat\
drowsiness
on the highway as an emergency.
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CAUTION
It can be dangerous to get out of your vehicle if the shift lever is not
fully in
P (Park) with the parking brake firmly set. Your vehicle can
roll.
If you have left the engine running, the vehicle can move suddenl\
y.
You
or others could be injured. To be sure your vehicle won’t move,
when you’re on fairly level ground, use the steps that follow.
If you have four-wheel drive and your transfer case is in N (Neutral),
your vehicle will be free to
roll, even if your shift lever is in P (Park).
So, be sure the transfer case is in a drive gear-not in N (Neutral).
If you are parking on a hill, or if you’re pulling a trailer, also see
“Parking On Hills” in the Index.
When You Are Ready to Leave After Parklng on a Hill
1. Apply your regular brakes and hold the pedal down while you:
Start your engine;
Shift into a gear; and
Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer To wing
Your vehicle will need service more often when you’re pulling a trailer. See
the Maintenance Schedule for more on this. Things that are esp\
ecially
important in trailer operation are automatic transmission fluid (don’t overfill),
engine oil, axle lubricant, belts, cooling system, and brake ad\
justment. Each
of these is covered in this manual, and the Index will help \
you find them
quickly.
If you’re trailering, it’s a good idea to review these sections before
you start your trip.
Check periodically
to see that all hitch nuts and bolts are tight.
mailer Wiring Harness
See “Trailer Wiring Harness’’ in the Index.
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