1996 GMC SIERRA engine

Driving Downhill
When off-roading takes you downhill, you’ll want to
consider
a number of things:
How steep is the downhill? Will I be able to maintain
vehicle control?
What’s the surface like? Smooth? Rough? Slippery?
Hard-packed dirt? Gravel?
Logs? Boulders?
Are there hidden surface obstacles? Ruts?
What’s at the bottom of the hill‘? Is there a hidden
creek bank or even a river bottom
with large rocks?
If you decide YOU can go down a hill safely, then try to
keep your vehicle headed straight down, and use a low
gear. This way, engine drag can help your brakes and
they won’t have to do all
the work. Descend slowly,
keeping your vehicle under control at all times,
’ A CAUTION:
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Heavy braking when going down a hill can
cause your brakes to overheat and fade. This
could cause loss
of control and a serious accident.
Apply the brakes lightly when descending
a
hill and use a low gear to keep vehicle speed
under control.
Are there some things
I should not do when
driving down a hill?
At Yes! These are important because if you ignore them
you could lose control and have a serious accident.
0 When driving downhill, avoid turns that take you
across the incline
of the hill. A hill that’s not too
steep to drive down may be too steep to drive across.
You could roll over if you don’t drive straight down.
0 Never go downhill with the transmission in
NEUTRAL (N), or with the clutch pedal depressed
in a manual shift, This is called “free-wheeling.”
Your brakes will have to
do all the work and could
overheat and fade.
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Am I likely to stall when going downhill?
A: It’s much more likely to happen going uphill. But
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if it happens going downhill, here’s what to do.
Stop your vehicle by applying the regular brakes.
Apply
the parking brake.
Shift
to PARK (P) (or to NEUTRAL (N) with the
manual transmission) and, while still braking, restart
the engine.
Shift back
to a low gear, release the parking brake,
and drive straight down.
If the engine won’t start, get out and get help.
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:
0 A hill that can be driven straight up or down 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.
0 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.
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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. Driving mrough rushing water can be dangerous.
Deep water can sweep your vehicle downstream
and you and your passengers could drown.
If it’s
only shallow water, it can still wash away the
ground from under your tires, and you could lose
traction and roll the vehicle over. Don’t drive
through rushing water.
See “Driving Through Water” in the Index for more
information on driving through water.
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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 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 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.
“Tires” in the Index.)
Have good tires with proper tread depth. (See
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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 YOLI need it.
Here are some things you can check before a trip:
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Windshield Wnslwr FILd: Is the reservoir full? Are
all windows clean inside and outside?
Wiper Blades: Are they in good shape‘?
F~lel, Engine Oil, Other Fluids: Have you checked
all levels?
Lnmps: 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?
Mqx: Do you have up-to-date maps?
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‘--b hway 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
thun CI secmd, 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.
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.)
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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.
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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~h CAUTION:
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.
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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If You’re Caught in a Blizzard
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Tie a red cloth to your vehicle to alert police that
you’ve been stopped
by the snow.
If
you are stopped by heavy snow, you could be in a
serious situation.
You should probably stay with your
vehicle unless you know for sure that you are near help
and
you can hike through the snow. Here are some
things to
do to summon help and keep yourself and your
passengers safe:
Turn on your hazard flashers.
Put on extra clothing or wrap a blanket around you.
If you have no blankets or extra clothing, make body
insulators from newspapers, burlap bags, rags, floor
mats
-- anything you can wrap around yourself or
tuck under your clothing
to keep warm.
You can run the engine to keep warm, but be careful.
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