1997 GMC SIERRA Owners Manual

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 hydroplaning,
it has little or no contact with the road.
Hydroplaning doesn’t happen often. But it can if your
tires
do not have 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 surface, 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.
Driving Through Deep Standing Water
NOTICE:
If you drive too quickly through deep puddles
or standing water, water can come in through
your engine’s air intake and badly damage your engine. Never drive through water that is slightly
lower than the underbody
of your vehicle. If you
can’t avoid deep puddles or standing water, drive
through them very slowly.
Some Other Rainy Weather Tips
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.
0 Have good tires with proper tread depth. (See “Tires” in the Index.)
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City Driving 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.
Try to use the freeways that rim and crisscross most
large cities.
You’ll save time and energy. (See the
next
part, “Freeway Driving.”)
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.
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.
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Freeway Driving
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 driving. Too-fast or
too-slow driving breaks a smooth traffic flow. Treat the
left lane on a freeway as a passing lane.
At the entrance, there is usually a ramp that leads to the
freeway. 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. Try to merge into the gap at close to
the prevailing speed. Switch on your turn signal, check
your mirrors and glance over your shoulder as often as
necessary. Try to blend smoothly with the traffic flow.
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 unless you want to pass.
Before changing lanes, check your mirrors. Then use
your 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.
Once you
are moving on the freeway, make certain you
allow a reasonable following distance. Expect to move
slightly slower at night.
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When you want to leave the freeway, move to the proper
lane well in advance. If you miss your exit, do not,
under any circumstances,
stop and back up. Drive on
to the next exit.
The exit ramp can be curved, sometimes 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.
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
GM
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:
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Windshield Washer Fluid: Is the reservoir full?
Are all windows clean inside and outside?
Wiper Blades: Are they in good shape?
Fuel, Engine Oil, Other Fluids: Have you checked
all levels?
Lamps: 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?
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?
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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
same 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:
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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 mirrors and your
instruments frequently.
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.
Hill and Mountain Roads
Driving on steep hills or mountains is different from
driving in flat or rolling terrain.
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If you drive regularly in steep country, or if you’re
planning to visit there, here are some tips
that can make
your trips safer and more enjoyable. (See “Off-Road
Driving” in the Index for information about
driving off-road.)
0 Keep your vehicle in good shape. Check all fluid
levels and also
the brakes, tires, cooling system and
transmission. These
parts can work hard on
mountain roads.
0 Know how to go down hills. The most important
thing
to know is this: let your engine do some of the
slowing down. Shift to a lower gear when you go
down a steep or long hill.
If you don’t shift down, your brakes could get
so hot that they wouldn’t work well. You would
then have poor braking or even none going
down a hill. You could crash. Shift down to let
your engine assist your brakes on a steep
downhill slope.
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Coasting downhill in NEUTRAL (N) or with the
ignition
off is dangerous. Your brakes will have to
do all the work of slowing down. They could get
so hot that they wouldn’t work well. You would
then have poor braking or even none going down
a hill.
You could crash. Always have your engine
running and your vehicle in gear when you
go downhill.
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Know how to go uphill. You may want to shift down
to
a lower gear. The lower gears help cool your engine
and transmission,
and you can climb the hill better.
Stay
in your own lane when driving on two-lane
roads in hills or mountains. Don’t swing wide
or cut
across the center
of the road. Drive at speeds that let
you stay in your own lane.
As you go over the top of a hill, be alert. There could be
something
in your lane, like a stalled car or an accident.
You may see highway signs on mountains that warn of
special problems. Examples are long grades, passing or
no-passing zones, a falling rocks area or winding
roads. Be alert
to these and take appropriate action.
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Winter Driving
Here are some tips for winter driving:
0 Have your vehicle in good shape for winter.
You may want to put winter emergency supplies in
your vehicle. Include
an ice scraper, a small brush or broom, a supply
of windshield washer fluid, a rag, some winter outer
clothing, a small shovel,
a flashlight, a red cloth and
reflective warning triangles. And, if you will be driving
under severe conditions, include a small bag of sand, a
piece of old carpet or a couple
of burlap bags to help
provide traction. Be sure you properly secure these
items in your vehicle.
Driving on Snow or Ice
Most of the time, those places where your tires meet the
road probably have good traction.
However,
if there is snow or ice between your tires and
the road, you can have a very slippery situation. You’ll
have a lot less traction or
“grip” and will need to be
very careful.
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What’s the worst time for this? “Wet ice.” Very cold
snow or ice can be slick and hard to drive on. But wet
ice can be even more trouble because it may offer the
least traction of all. You can get wet ice when it’s about
freezing
(32°F; 0°C) and freezing rain begins to fall.
Try to avoid driving on wet ice until salt and sand crews
can get there.
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Whatever the condition -- smooth ice, packed, blowing
or loose snow
-- drive with caution.
Accelerate gently.
Try not to break the fragile traction. If
you accelerate too fast, the drive wheels will spin and
polish the surface under the tires even more.
Your anti-lock brakes improve your vehicle’s stability
when you make a hard stop on a slippery road. Even
though you have an anti-lock braking system, you’ll
want to begin stopping sooner than you would on
dry
pavement. See “Anti-Lock” in the Index.
Mow greater following distance on any slippery road.
Watch for slippery spots. The road might be fine
until you hit a spot that’s covered with
ice. On an
otherwise clear road, ice patches may appear in
shaded areas where the sun can’t reach: around
clumps of trees, behind buildings or under bridges.
Sometimes the surface
of a curve or an overpass may
remain icy when the surrounding roads are clear. If
you see a patch
of ice ahead of you, brake before you
are on it.
Try not to brake while you’re actually on
the ice, and avoid sudden steering maneuvers.
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