1997 GMC SIERRA engine

Driving Downhill
When off-roading takes you downhill, you 11 want to
consider
a number of things:
How steep is the downhill? Will I be able to maintain
What’s the surface like? Smooth? Rough? Slippery?
Are there hidden surface obstacles? Ruts? Logs?
What’s at the bottom of the hill? Is there a hidden
vehicle control?
Hard-packed dirt? Gravel?
Boulders?
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.
I a CAUTIO, .:
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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
A: Yes! These are important because if you ignore them
driving down a hill?
you could lose control and have a serious accident.
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.
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 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.
e 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 incl.ine. Here are some
things to consider:
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
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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.
Driving across an incline that’s too steep will
make your vehicle roll over.
You could be
seriously injured or killed.
If you have any doubt
about the steepness
of the incline, don’t drive
across it. Find another route instead.
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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.
ki CAU IN:
Driving through 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.
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.
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
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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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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If You’re Caught in a Blizzard a 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.
0 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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