1993 GMC SIERRA engine

Tune your senses to different kinds of signals. -Your eyes, for example, meed
to constantly sweep the terrain for unexpected obstacles. Your .ears need
to
listen for unusual tire or engine sounds. With your arms, hands, feet, and
body you’ll need to respond
to vibrations and vehicle bounce.
Controlling your vehicle is the key
to successful off-road driving. One of the
best ways
to control your vehicle is to control your speed. Here .are some
things
to keep in mind. At higher speeds:
e you approach things fastar and you have less time to scan the terrain
for obstacles.
you have less time
to react. ‘I , ’C _. ’.
you have more vehicle bounce when you drive over obstacles.
you’ll need more distance for braking, especially since you’\
re on an unpaved surface.
CAUTION
When you’re driving off road, bouncing and quick changes in
direction can easily throw you out of position. This could cause you
to lose control and crash. So, whether you’re driving on or off the
road, you and your passengers should wear safety belts.
Scanning the Terrain
Off-road driving can take you over many different kinds of terrain. You need
to be familiar with the terrain and its many different features. Here are some
things
to consider.
Surface Conditions
Off-roading can ta.ke you. over hard-packed dirt, gravel, rocks,\
grass, sand, mud, snow or ice. Each of these sutfaces affects the steering, acceleration,
and braking of your vehicle in different ways. Depending upon the kind of
. surface you are on, you may experience slipping, sliding, wheel\
spinning,
delayed acceleration, poor traction, and longer braking distances\
.
Surface Obstacles
Unseen or hidden obstacles can be hazardous. A rock, log, hole, rut, or
bump can startle you if you’re not prepared for them. Often these obstacles
are hidden by grass, bushes, snow or even the rise and fall of the terrain
itself. -.Here are some things
to consider:
Is the path ahead clear?
Will the surface texture change abruptly up ahead?
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Your Driving and the Road
A Turning or driving across steep hills can be dangerous. You could
lose traction, slide sideways, and possibly roll over. You could be
seriously injured or
I 'I' ?d. When driving up hills, always try to go
I straight up.
Ease up on your speed as you approach the top of the hill.
Attach a flag to the vehicle to make you more visible to approaching
traffic on trails or hills.
Sound the horn as you approach the top of hill to let opposing traffic
know you're there.
Use your headlights even during the day. They make you more visible to
oncoming traffic.
I A Driving to the top (crest) of a hill at full speed can muse an
accident.
There could be a drop-off, embankment, cliff, or even
another vehicle. You buld be seriously injured or killed. .As you near
the
top of a hill, slow down and stay alert. I
Q: What should I do if my vehicle stalls, or is about to stall, and I can't
make it
up the hill?
A: If this happens, there are some things you should do, and there are some
things
you must not do. First, here's what you should do:
0
0
0
0
Push the brake pedal to stop the vehicle and keep it from rolling
backwards.
Also, apply the parking brake.
If your engine is still running, shift the transmission into reverse, release
the parking brake, and slowly back down the hill in reverse.
If your engine has stopped running, you'll need to restart it. With the
brake pedal depressed and the parking brake still applied, shift the
transmission to
P (Park) (or, shift to N (Neutral) if your vehicle has a
manual transmission) and restart the engine. Then, shift to Reverse,
release the parking brake, and slowly back down the hill in reverse.
As you are backing down the hill, put your left hand on the ste\
ering
wheel at the
12 o'clock position. This way, you'll be able to tell if your
wheels are straight or turned to the left or right as you back down.
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Here are some things you must not do if you stall, or are about to stall,
when going up a hill.
Never attempt to prevent a stall by shifting into N (Neutral) (or
depressing the clutch,
if you have a manual transmission) to “rev-up” the
engine and regain forward momentum. This won’t work. Your vehicle will
roll backwards very quickly and you could go out of control.
Instead, apply the regular brake to stop the vehicle. Then apply the parking
brake. Shift into reverse, release the parking brake, and slowl\
y back down.
Never attempt to turn around if you are about to stall when going up a
hill. If the hill is steep enough to stall your vehicle, it’s steep enough to
cause you. to roll over
if you turn around. If you can’t make it up the
hill, you must back down the hill.
Q: Suppose, after stalling, I try to back down the hill and decide I just
can’t
do it. What should I do?
A: Set the parking brake, put your transmission in P (Park) (or the manual
transmission in first gear), and turn off the engine. Leave the vehicle and \
go
get some help. Exit on the uphill side and stay clear of the\
path the vehicle
would take
if it rolled downhill. Do not shift the transfer case to N (Neutral)
when you leave the vehicle. Leave it in some gear.
Shifting the transfer case to
N (Neutral) can cause your vehicle to
roll even
if the transmission is in P (Park) (or, if you have the
manual transmission, even
if you’re in gear). This is because the N
(Neutral) position on the transfer case overrides the transmis\
sion. If
you are going to leave your vehicle, set the parking brake and shi”
the transmission to
P (Park) (or, put your manual transmission in f
gear). But do not shift the transfer case to the N (Neutral) positior
Leave the transfer case in the
2 Wheel, 4 High or 4 Low position.
1
Lriving 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? Grave
I?
Are there hidden surface obstacles? Ruts? Logs? Boulders?
What’s at the bottom
of the hill? Is there a hidden creek bank or even a
river bottom with large rocks?
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Your Driving and the Road
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 dr\
ag can help
your brakes and they won’t have to do
all the work. Descend slowly, keeping
your vehicle under control at all times.
CAUTION
A 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.
Q: Are there some things I should not do when driving down a hili?
A: Yes! These are important because if you ignore them you could lose
control and have a serious accident.
When driving downhill, avoid turns that take you across the in\
cline 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 N (Neutral), or with the clutch
pedal depressed in a manual shift. This is called “free-whee\
ling,” Your
brakes will have
to do all the work and could overheat and fade.
Avoid braking so hard that you lock the wheels when going downhill. If
your front wheels are locked, you can’t steer your vehicle. \
If your wheels
lock up during downhill braking, you may feel the vehicle star\
ting to slide
sideways.
To regain your direction, just ease off the brakes and steer to
keep the front of the vehicle pointing straight downhill.
Q: 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 pa\
rking
brake.
Shift to P (Park) (or to Neutral 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.
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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.
Hard packed snow and ice offer the worst tire traction. On th\
ese surfaces, it’s
very easy to lose control. On wet ice, for example, the tract\
ion
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.
I A Driving on frozen lakes, ponds or rivers can be dangerous. I
Underwater springs, currents under the ice, or sudden thaws can
weaken the ice. Your vehicle could fall through the ice and you and
your passengers could drown. Drive your vehicle on
safe surfaces
on
I y.
.
Driving In Water
Light rain causes no special off-road driving problems. But hea\
vy 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. S\
talling can also
occur
if you get your tailpipe under water. And, as long as your tailp\
ipe is
under water, you’ll never be able to start your engine. Whe\
n you go through
water, remember that when your brakes get wet, it may take you longer to
stop.
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 inches deep, it can still wash away the ground
from under your tires, and you could lose traction and roll t\
he vehicle
over. Don’t drive throuah rushina water. I
If you have a diesel engine, see “Driving Through Water (Diese\
l Engines)” in
the Index for more information on driving through water.
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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.
.. . .- , - .~
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.
-
,x ! - : ,-.:.&---z-.- ..* .-7
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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As in any driving situation, keep pace with traffic and allow adequat\
e
following distances.
Hill and Mountain Roads
I r
AM470001
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” in the Index for information about driving off-road.)
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. Don’t make your brakes do it
all. Shift to a lower gear when you go down a steep or long hill. That
way, you will slow down without excessive use of your brakes.
If you don’t shift down,’ your brakes could get so hot that they
- b 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. I I
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