1994 GMC SIERRA Owners Manual

Driving Across an Incline
Sooner or later, an off-road trail will probably go across the incline of a hill.
If this happens, you have to decide whether to try to drive across the incline.
Here are some things
to consider:
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A hill that can be driven straighr: up or aown may be too steep to drive
across. When you go straight
up or down a hill, the length of the wheel
base (the distance from the front wheels to the rear wheels) reduces the
likelihood the vehicle will tumble end over end. But when you drive
across an incline, the much more narrow track width (the distance
between the
left and right wheels) may not prevent the vehicle from
tilting and rolling over. Also, driving across an incline puts more
weight on the downhill wheels. This could cause
a downhill slide or a
rollover.
Surface conditions can be
a problem when you drive across a hill.
Loose gravel, muddy spots, or even wet grass can cause your tires to
slip sideways, downhill. If the vehicle slips sideways,
it can hit
something that will trip it (a rock, a rut, etc.) and roll over.
Hidden obstacles can make the steepness of the incline even worse. If
you drive across a rock with the uphill wheels, or if the downhill
wheels drop into a rut or depression, your vehicle can tilt even more.
For reasons
like these, you need to decide carefully whether to try to drive
across an incline. Just because the trail goes across the incline doesn’t mean
you have
to drive it. The last vehicle to try it might have rolled over.
Q: What if I’m driving across an incline that’s not too steep, but I hit
A: If you feel your vehicle starting to slide sideways, turn downhill. This
should help straighten out the vehicle and prevent the side slipping.
However, a much better way
to prevent this is to get out and “walk the
course”
so you know what the surface is like before you drive it.
some loose gravel and start to slide downhill. What should I do?
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Stalling on an Incline
If your vehicle stalls when you’re crossing an incline, be sure you (and your
passengers) get out on the uphill side, even
if the door there is harder to
open. If
you get out on the downhill side and the vehicle starts to roll over,
you’ll be right in its path.
If you have to walk
down the slope, stay
out
of the path the
vehicle will take if
it
does roll over.
Driving In Mud, Sand, Snow, Or Ice
When you drive in mud, snow or sand, your wheels won’t get good traction.
You can’t accelerate as quickly, turning
is more difficult, and you’ll need
longer braking distances.
It’s best to use
a low gear when you’re in mud - the deeper the mud, the
lower
the gear. In really deep mud, the idea is to keep your vehicle moving
so you don’t get stuck.
When you drive
on sand, you’ll sense a change in wheel traction. But it will
depend upon how loosely packed the sand is. On loosely packed sand
(as on
beaches or sand dunes) your tires
will tend to sink into the sand. This has an
effect
on steering, accelerating, and braking. You may want to reduce the air
pressure
in your tires slightly when driving on sand. This will improve
traction.
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Hard packed snow and ice offer the worst tire traction. On these surfxes,
it’s very easy to lose control. On wet ice, for example, the traction
is so poor
that you will have difficulty accelerating. And
if you do get moving, poor
steering and difficult braking can cause you to slide out of control.
Driving In Water
Light rain causes no special off-road driving problems. But heavy rain can
mean flash flooding, and flood waters demand extreme caution.
Find out how deep the water is before you drive through it. If it’s deep
enough to cover your wheel hubs, axles, or exhaust pipe, don’t try
it - you
probably won’t get through.
Also, water that deep can damage your axle and
other vehicle parts.
If the water isn’t too deep, then drive through it slowly. At fast speeds, water
splashes on your ignition system and your vehicle can stall. Stalling can
also
occur if you get your tailpipe under water. And, as long as your tailpipe is
under water, you’ll never be able
to start your engine. When you go through
water, remember that when your brakes get wet, it may take you longer to
stop.
If you have
a diesel engine, see “Driving Through Water (Diesel Engines)”
in the Index for more information
on driving through water.
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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 the body
structure, steering, suspension, wheels, tires, and exhaust system 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 the Maintenance Schedule for additional information.
Driving at Night
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.
Don’t drink and drive.
a Adjust your inside rearview mirror to reduce the glare from headlights
behind you.
Since you can’t see as well, you may need to slow down and keep more
space between you and other vehicles.
Slow down, especially on higher speed roads. Your headlights can light
up only so much road ahead.
In remote areas, watch for animals.
If you’re tired, pull off the road in a safe place and rest.
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Nighf 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. They may cut down
on glare from
headlights, but they also make a lot of things invisible.
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 misairned headlights), slow down a little. Avoid
staring directly into the approaching lights.
Keep your windshield and all the glass on your vehicle clean
- inside and
out. Glare at night is made much worse by dirt
on the glass. Even the inside
of the glass can build up a film caused by dust. Dirty glass makes lights
dazzle and flash more than clean glass would, making
the pupils of your
eyes contract repeatedly.
Remember that
your headlights light up fir less of a roadway when you are
in a turn or curve. Keep your eyes moving; that way, it’s easier to pick out
dimly lighted objects. Just
as your headlights should be checked regularly
for proper aim,
so should your eyes be examined regularly. Some drivers
suffer from night blindness
- the inability to see in dim light - and aren’t
even aware
of it.
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Driving in the Rain
Rain and wet roads can mean driving trouble. On a wet road y\
ou can’t stop,
accelerate or turn as well because your tire-to-road traction isn’t as good as
on dry roads. And, if your tires don’t have much tread left, \
you’ll get even
less traction.
It’s always wise to go slower and be cautious if rain starts to
fall while you are driving. The surface may get wet suddenly when \
your
reflexes
are tuned for driving on dry pavement.
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.
It’s wise to keep your wiping equipment in good shape and \
keep your 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.
Hydroplaning
Hjdroplaning is dangerous. So much water can build up under your tires
that they can actually ride on the water. This caa happen if the road is wet
enough and you’re going fast enough. When your vehicle
is hydroplaning, it
has little or no contact with the road.
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 sudace, there
could be hydroplaning.
Hydroplaning usually happens at higher speeds. There just isn’t a hard and
fast rule about hydroplaning. The best advice is to slow down when
it is
raining.
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Some Other Rainy Weather Tips
0 Turn on your low-beam headlights - not just your parking llgnts - to
help make you more visible to others.
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.
Have good tires with proper tread depth. (See “Tires” in the Index.)
City Driving
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 pay
attention to traffic signals.
Here are ways to increase your safety
in city driving:
Know the best way to get to where you are going. Get a city map and
plan your trip
into an unknown part of the city just as you would for a
cross-country trip.
save time and energy. (See the
next section, “Freeway Driving.”)
0 Try to use the freeways that rim and crisscross most large cities. You’ll
0 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.
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