1993 GMC SIERRA Owners Manual

The heavier the rain, the harder it is to see. Even if your windshield wiper
blades are in good shape, a heavy rain can make it harder to see road signs
and traffic signals, pavement markings, the edge of the road, and even
people walking. Road spray can often be worse for vision than \
rain,
especially
if it comes from a dirty road.
So it is wise to keep your wiping equipment in good shape and keep you\
r
windshield washer tank filled. Replace your windshield wiper ins\
erts when they show signs of streaking or missing areas on the windshield,
or when strips of
rubber start
to separate from the inserts.
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Driving too fast through large water puddles or even going through some car
washes can cause problems,
too. The water may affect your brakes. Try to
avoid puddles. But
if you can't, try to slow down before you hit them.
Wet brakes can cause accidents. They won't work well in a quick
d stop and may cause pulling to one side. You could lose control of
the vehicle.
After driving through a large puddle of water or a car wash, apply
your brake pedal lightly until your brakes work normally.
Hydroplaning
Hydroplaning is dangerous. So much water can build up under your tires that
they can actually ride on the water. This can happen
if the road is wet
enough and you're going fast enough. When your vehicle is hydr\
oplaning,
it
has little or no contact with the road.
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Your Driving and the Road
You might not be aware of hydroplaning. You could drive along for some time
without realizing your tires aren’t in constant contact with \
the road. You could
find out the hard way: when you have to slow, turn, move out to pass-or
if
you get hit by a gust of wind. You could suddenly find yourself out of control.
Hydroplaning doesn’t happen often. But it can
if your tires haven’t much tread
or if the pressure in one or more is low. It can happen if a lot of water is
standing
on the road. If you can see reflections from trees, telephone poles,
or other vehicles, and raindrops “dimple” the water’s surfa\
ce, there could be
hydroplaning.
Hydroplaning usually happens on higher speed roads. There just \
isn’t a hard
and fast rule about hydroplaning. The best advice is to slow \
down when it is
raining, and be careful.
Some Other Rainy Weather Tips
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Turn on your headlights-not just your parking lights-to help ma\
ke you more visible to others.
Look for hard-to-see vehicles coming from behind. You may want to use
your headlights even in daytime
if it’s raining hard.
Besides slowing down, allow some extra following distance. And \
be
especially careful when you pass another vehicle.
Allow yourself more
clear
room ahead, and be prepared to have your view restricted by road
spray.
If the road spray is so heavy you are actually blinded, drop back.
Don’t pass until conditions improve. Going more slowly is be\
tter than
having an accident.
Use your defogger
if it helps.
Have good tires with proper tread depth. (See “Tires” in\
the Index.)
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Driving in Fog, Mist and Haze
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Fog can occur with high humidity or heavy frost. It can be so mild that you
can see through it for several hundred feet (meters). Or it might be
so thick
that you can see only a few feet (meters) ahead.
It may come suddenly to
an otherwise clear road. And it can be a major hazard.
When you drive into a fog patch, your visibility will be reduced quickly. The
biggest dangers are striking the vehicle ahead or being struck \
by the one
behind.
Try to “read” the fog density down the road. If the vehicle ahead
starts to become
less clear or, at night, if the taillights are harder to see, the
fog is probably thickening. Slow down to give traffic behind you a chance to
slow down. Everybody then has a better chance to avoid hitting the vehicle
ahead.
A patch of dense fog may extend only for a few feet (meters) or for miles
(kilometers); you can’t really tell while you’re in it. You can only treat the
situation with extreme care.
One common fog condition-sometimes called mist or ground fog-can
happen in weather that seems perfect, especially at night or i\
n the early
morning
in valley and low, marshy areas. You can be suddenly enveloped in
thick, wet haze that may even coat your windshield. You can often spot t\
hese
fog patches or mist layers with your headlights. But sometimes \
they can be waiting for you as you come over a hill or dip into a shallow valley. Start
your windshield wipers and washer, to help clear accumulated ro\
ad dirt.
Slow
down carefully.
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Your Driving and the Road
Tips on Driving in Fog
If you get caught in fog, turn your headlights on low beam, \
even in daytime.
You’ll see-and be seen-better. Use your fog lights
if your vehicle has them.
Don’t use your high beams. The light will bounce
off the water droplets that
make up fog and reflect back at you.
Use your defogger. In high humidity, even a light buildup of moisture on the
inside of the glass will cut down on your already limited visibility. Ru\
n your
windshield wiper and washer occasionally. Moisture can build up on the
outside glass, and what seems to be
fog may actually be moisture on the
outside of your windshield.
Treat dense fog as an emergency.
Try to find a place to pull off the road. Of
course you want to respect another’s property, but you might need to put
something between you and moving vehicles-space, trees, telephone\
poles,
a private driveway, anything that removes you from other traffic.
If visibility is near zero and you must stop but are unsure whether you are
away from the road, turn your lights on, start your hazard wa\
rning flasher,
and sound your horn at intervals or when you hear approaching \
traffic.
Pass other vehicles in fog only
if you can see far enough ahead to pass
safely. Even then, be prepared to delay your pass
if you suspect the fog is
worse up ahead. If other vehicles try to pass you, make it easy for them.
City Driving
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One of the biggest problems with city streets is the amount of traffic on them.
You’ll want to watch out for what the other drivers are doing, and keep clos\
e
track
of traffic signals.
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Here are ways to increase your safety in city driving:
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Know the best way to get to where you are going. Try not to drive
around trying to pick out a familiar street or landmark. Get a city map
and plan your trip into an unknown part of the city just as you would for
a cross-country trip.
Try to use the freeways that rim and crisscross most large cities. You’ll
save time and energy. (See the next section, “Freeway Drivi\
ng.”)
Treat a green light as a warning signal.
A traffic light is there because
the corner is busy enough to need it. When a light turns green, and just
before you start to move, check both ways for vehicles that have not
cleared the intersection or may be running the red light.
Obey all posted speed limits. But remember that they are for ideal road,
weather and visibility conditions. You may need to drive below the
posted limit in bad weather or when visibility is especially poor.
Pull to the right (with care) and stop clear of intersections when you see
or hear emergency vehicles.
Freeway Driving
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Mile for mile, freeways (also called thruways, parkways, expressways,
turnpikes, or superhighways) are the safest of all roads. But \
they have their
own special rules.
The most important advice on freeway driving is: Keep up with \
traffic and keep to the right. Drive at the same
speed most of the other drivers are
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Your Driving and the Road
driving. Too-fast or too-slow driving breaks a smooth traffic flow. Treat the left
lane on a freeway as a passing lane.
Entering the Freeway
At the entrance there is usually a ramp that leads to the freewa\
y. If you have
a clear view of the freeway as you drive along the entrance ramp, you
should begin to check traffic.
Try to determine where you expect to blend
with the flow.
If traffic is light, you may have no problem. But if it is heavy,
find a gap as you move along the entering lane and time your approach. T\
ry
to merge into the gap at close to the prevailing speed. Switc\
h on your turn signal, check your rearview mirrors as you move along, and gla\
nce over your
shoulder as often as necessary.
Try to blend smoothly with the traffic flow.
Driving on the Freeway
Once you are on the freeway, adjust your speed to the posted \
limit or to the
prevailing rate if it’s slower. Stay in the right lane unle\
ss you want to pass.
If
you are on a two-lane freeway, treat the right lane as the slow lane and the
left lane as the passing lane. If you are on a three-lane fr\
eeway, treat the
right lane as the slower-speed through lane, the middle lane a\
s the
higher-speed through lane, and the left lane as the passing la\
ne.
Before changing lanes, check your rearview mirrors. Then use yo\
ur turn
signal. Just before you leave the lane, glance quickly over
your shoulder to
make sure there isn’t another vehicle in your “blind” \
spot.
If you are moving from an outside to a center lane on a freeway having
more than two lanes, make sure another vehicle isn’t about \
to move into the
same spot. Look at the vehicles
two lanes over and watch for telltale signs:
turn signals flashing, an increase in speed, or moving toward \
the edge of the lane. Be prepared to delay your move.
Once you are moving on the freeway, make certain you allow a \
reasonable
following distance. Expect to move slightly slower at night.
Leaving the Freeway
When you want to leave the freeway, move to the proper lane \
well in
advance. Dashing across lanes at the last minute is dangerous. \
If you miss
your exit do not, under any circumstances, stop and back up. \
Drive on to the next exit.
At each exit point is a deceleration lane. Ideally it should be long enough for
you to enter
it at freeway speed (after signaling, of course) and then do yo\
ur
braking before moving onto the exit ramp. Unfortunately, not all deceleration
lanes are long enough-some are too short for all the braking. \
Decide when
to start braking.
If you must brake on the through lane, and if there is traffic
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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.
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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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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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