engine GMC SIERRA 1994 Service Manual

You’ll find other important information in this manual. See “Vehicle
Loading,” “Luggage Carrier’’ and “Tires”
in the Index.
Traveling to Remote Areas
It makes sense to plan your trip, especially when going to a remote area.
Know the terrain and plan your route. You are much less likely to get bad
surprises. Get accurate
maps of trails and terrain. Try to learn of any
blocked or closed roads.
It’s
also a good idea to travel with at least one other vehicle. If something
happens
to one of them, the other can help quickly.
Does your vehicle have a winch? If
so, be sure to read the winch
instructions. In a remote area, a winch can be handy
if you get stuck. But
you’ll want to know how
to use it properly.
Getting Familiar with Off-Road Driving
It’s a good idea to practice in an area that’s safe and close to home before
you
go into the wilderness. Off-road driving does require some new and
different driving skills. Here’s what we mean.
Tune your senses to different kinds of signals. Your eyes, for example, need
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.
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Q: What should I do if my vehicle stalls, or is about to stall, and I
can’t make
it up the hill?
A:
0
a
a
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
slzould do:
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 as straight as
possible
in reverse.
As you are backing down the hill, put your left hand on the steering
wheel at the
12 o’clock position. This way, you’ll be able to tell if your
wheels are straight and maneuver as you back down. It’s best that you
back down the
hill with your wheels straight rather than in the left or
right direction. Turning the wheel too far to the left or right will
increase the possibility of
a rollover.
Here are some things
you mist nof 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.
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Instead, apply the regular brake to stop the vehicle. Then apply the parking
brake. Shift into reverse, release the parking brake, and slowly back straight
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 straight 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.
Driving Downhill
When off-roading takes you downhill, you’ll want to consider a number of
things:
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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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:
Heavy braking when going down a hill can cause your brakes to
overheat and fade. This could cause loss of control and a ser\
ious
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 hill?
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 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 “N” (Neutral) , 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.
Avoid braking so hard that you lock the front 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 starting
to slide sideways. To regain your direction, just ease off
the brakes and steer to keep the front of the vehicle pointing straight
downhill.
0: 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.
0 Stop your vehicle by applying the regular brakes. Apply the parking
brake.
Shift to ‘bP’ (Park) (or to Neutral with the lnanual transmission) and,
while still braking, restart the engine.
0 Shift back to a low gear, release the parking brake, and drive straight
down.
0 If the engine won’t start, get out and get hclp.
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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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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 Vehicle
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
inside and outside?
Wiper Blades: Are they in good shape‘?
Fuel, Engine Oil, Other Fluids: Have you checked all levels?
0 Lights: Are they all working? Are the lenses clean‘?
0 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‘?
0 Weather Forecasts: What’s the weather outlook along your route?
Should you delay your trip
a short time to avoid a major storm system?
0 Maps: Do you have up-to-date maps?
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.
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What can you do about highway hypnosis? First, be aware that it can
happen.
Then here are some tips:
0 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.
0 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.)
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.
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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
, 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
0 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. your lane, like a stalled car or an accident.
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Winter Driving
Here are some tips for winter driving:
Have your Vehicle in good shape for winter. Be sure your engine
coolant mix
is correct.
0 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 a couple of 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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If You’re Caught in a Blizzard
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. Tie a red cloth to your vehicle
to alert police that you’ve
been stopped
by the snow, 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.
A CAUTION:
Snow can trap exhaust gases under your vehicle. This can cause
deadly
CO (carbon monoxide) gas to get inside. CO could
overcome you and kill you.
You can’t see it or smell it, so you
might not know
it is in your vehicle. Clear away snow from
around the base
of your vehicle , especially any that is blocking
your exhaust pipe. And check around again from time
to time to
be sure snow doesn’t collect there.
Open
a window just a little on the side of the vehicle that’s away
from the wind. This will help keep CO out.
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