1994 GMC SIERRA tires

When your headlights or parking lights are on, rotate the dial to the right of
your headlight switch up
to brighten, or down to dim, your transfer case
indicator light.
2H (2-Wheel High): This setting is for driving in most street and highway
situations. Your front axle is not engaged
in two-wheel drive.
4H (4-Wheel High): This setting engages your front axle to help drive your
vehicle. Use
4H when you need extra traction, such as on wet or icy roads,
or in most off-road situations.
N (Neutral): Shift to this setting only when your vehicle needs to be towed
or when using a power take-off.
4L (4-Wheel Low): This setting also engages your front axle to give you
extra power, but should be used only for off-road driving.
You can shift from
2H to 4H or from 4H to 2H while the vehicle is moving.
Your front axle will engage faster if you take your foot off of the accelerator
for a few seconds after you shift.
In extremely cold weather it may be
necessary to stop or slow the vehicle to shift
out of 2H.
To shift into or out of 4L or “N” (Neutral):
Slow the vehicle to a roll, about 1-3 mph (2-5 kdh) and shift your
transmission into neutral.
0 Shift the transfer case shift lever in one continuous motion.
Don’t pause
in “N” (Neutral) as you shift the transfer case into 4L, or your
gears could clash.
Remember that driving
in 4H or 4L may reduce fuel economy. Also, driving
in four-wheel drive on dry pavement could cause your tires to wear fdster
and make your transfer case harder to shift.
Front Axle Locking Feature
The front axle locks and unlocks automatically when you shift the transfer
case. Some delay
for the axle to lock or unlock is normal. If the outside
temperature is very hot, or the vehicle has been used under hard driving
conditions, there may be
a slight delay for the axle to unlock.
Whenever you are
in four wheel drive, the rear wheel anti-lock brake
system does not operate. The regular brake system operates normally. When
you shift back into two-wheel drive, the anti-lock brake system will
operate.
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Control of a Vehicle
You have three systems that make your vehicle go where you want it to go.
They are the brakes, the steering and
the accelerator. All three systems have
to do their work at the places where the tires meet
the road.
Sometimes,
as when you’re driving on snow or ice, it‘s easy to ask more of
those control systems than the tires and road can provide. That means you
can lose control of
your vehicle.
Braking
Braking action involves perceptiorz time and renction time.
First, you have to decide to push on the brake pedal. That’spemptiorz time.
Then you have to bring up your foot and do it. That’s reaction time.
Average reaction time is about 3/4 of a second. But that’s only an average. It
might be less
with one driver and as long as two 01- three seconds or more
with another. Age, physical condition, alertness, coordination, and eyesight
all play a part.
So do alcohol, drugs and frustration. But even in 34 of a
second, a vehicle moving at 60 mph ( 100 km/h) travels 66 feet (20 m). That
could be
a lot of distance in an emergency, so keeping enough space
between your vehicle and others is important.
And,
of course, actual stopping distances vary greatly with the surface of the
road (whether it’s pavement
or gravel); the condition of the road (wet, dry,
icy); tire tread; and the condition of your brakes.
Avoid needless heavy braking. Some people drive
in spurts - heavy
acceleration followed
by heavy braking - rather than keeping pace with
traffic. This is
a mistake. Your brakes may not have time to cool between
hard
stops. Your brakes will wear out much faster if you do a lot of heavy
braking.
If you keep pace with the traffic and allow realistic following
distances, you will eliminate a lot of unnecessary braking. That means better
braking and longer brake life.
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So, use a “squeeze” braking technique. This will give you maximum
braking while maintaining steering control. You do this by pushing on the
brake pedal with steadily increasing pressure. When you do,
it will help
maintain steering control. In many emergencies, steering can help
you more
than even the very best braking.
Steering
Power Steering
If you lose power steering assist because the engine stops or the system is
not functioning, you can steer but it will take much more effort.
Steering lips
Driving on Curves
It’s important to take curves at a reasonable speed.
A lot of the “driver lost control” accidents mentioned on the news happen
on curves. Here’s
why:
Experienced driver or beginner, each of us is subject to the same laws of
physics when driving on curves. The traction
of the tires against the road
surface makes
it possible for the vehicle to change its path when you turn
the front wheels.
If there’s no traction, inertia will keep the vehicle going in
the same direction. If you‘ve ever tried to steer a vehicle on wet ice, you’ll
understand this.
The traction you can get
in a curve depends on the condition of your tires
and the road surface, the angle at which the curve
is banked, and your
speed. While you’re
in a curve, speed is the one factor you can control.
Suppose you’re steering through
a sharp curve. Then you suddenly apply
the brakes. Both control systems
- steering and braking - have to do their
work where the tires meet the road. Adding the hard braking can demand
too much at those places.
You can lose control.
The same thing can happen
if you’re steering through a sharp curve and you
suddenly accelerate. Those
two control systems - steering and acceleration
- can overwhelm those places where the tires meet the road and make you
lose control.
What should you do
if this ever happens? Ease up on the brake or
accelerator pedal, steer the vehicle the way you want
it to go, and slow
down.
Speed
limit signs near curves warn that you should adjust your speed. Of
course, the posted speeds are based on good weather and road conditions.
Under less favorable conditions you’ll want to
go slower.
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Watch for traffic signs, pavement markings, and lines. If you can see a
sign
up ahead that might indicate a turn or an intersection, delay your
pass.
A broken center line usually indicates it’s all right to pass
(providing the road ahead is clear). Never cross
a solid line on your
side of the lane or
a double solid line, even if the road seems empty of
approaching traffic.
Do not get too close to the vehicle you want to pass while you’re
awaiting an opportunity. For one thing, following
too closely reduces
your area of
vision, especially if you’re following a larger vehicle.
Also, you won’t have adequate space if the vehicle ahead suddenly
slows or stops. Keep back
a reasonable distance.
When
it looks like a chance to pass is coming up, start to accelerate but
stay
in the right lane and don’t get too close. Time your move so you
will be increasing speed as the time comes to move into the other lane.
If the way is clear to pass,
you will have a “running start” that more
than makes up for the distance you would lose by dropping back. And
if something happens to cause you to cancel your pass, you need only
slow down and drop back again and wait for another opportunity.
If other cars are lined up to pass a slow vehicle, wait your turn. But
take care that someone isn’t trying to pass you
as you pull out to pass
the slow vehicle. Remember to glance over your shoulder and check
the blind spot.
Check your mirrors
, glance over your shoulder, and start your left lane
change signal before moving out of the right lane to pass. When
you
are far enough ahead of the passed vehicle to see its front in your inside
mirror, activate your right lane change signal and move back into the
right lane. (Remember that
if your right outside mirror is convex, the
vehicle
you just passed may seem to be farther away from you than it
really is.)
Try
not to pass more than one vehicle at a time on two-lane roads.
Reconsider before passing the
next vehicle.
Don’t overtake
a slowly moving vehicle too rapidly. Even though the
brake lights are not flashing,
it may be slowing down or start
If you’re being passed, make it easy for the following driver
ahead
of you. Perhaps you can ease a little to the right. ;ing to turn.
to get
Loss of Control
Let’s
review what driving experts say about what happens when the three
control systems (brakes, steering and acceleration) don’t have enough
friction where
the tires meet the road to do what the driver has asked.
In any emergency, don’t give up. Keep trying to steer and constantly seek
an
escape route or area of less danger.
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Skidding
In a skid, a driver can lose control of the vehicle. Defensive drivers avoid
most skids by taking reasonable care suited to existing conditions, and by
not “overdriving” those conditions. But skids are always possible.
The three types of skids correspond to your Vehicle’s three control systems.
In the braking skid your wheels aren’t rolling. In the steering or cornering
skid, too much speed or steering in
a curve causes tires to slip and lose
cornering force. And
in the acceleration skid too much throttle causes the
driving wheels to spin.
A cornering skid and an acceleration skid are best handled by easing your
foot off the accelerator pedal.
If your vehicle starts
to slide, ease your foot off the accelerator pedal and
quickly steer the way
you want the vehicle to go. If you start steering
quickly enough, your vehicle may straighten out. Always be ready for
a
second skid if it occurs.
Of course, traction is reduced when water, snow, ice, gravel,
or other
material is
on the road. For safety, you’ll want to slow down and adjust your
driving to these conditions.
It is important to slow down on slippery
surfaces because stopping distance
will be longer and vehicle control more
limited.
While driving
on a surface with reduced traction, try your best to avoid
sudden steering, acceleration, or braking (including engine braking by
shifting
to a lower gear). Any sudden changes could cause the tires to slide.
You may not realize the surface is slippery until your vehicle is skidding.
Learn to recognize warning clues
- such as enough water, ice or packed
snow
on the road to make a “mirrored surface” - and slow down when you
have any doubt.
Remember: The rear-wheel anti-lock braking system (RWAL) helps avoid
only
a rear braking skid. In a braking skid (where the front wheels are no
longer rolling), release enough pressure
on the brakes to get the front wheels
rolling again. This restores steering control. Push the brake pedal down
steadily when you have
to stop suddenly. As long as the front wheels are
rolling, you
will have steering control.
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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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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:
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A hill that can be driven straighr: up or aown 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.
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.
Q: What if I’m driving across an incline that’s not too steep, but I hit
A: If you feel your vehicle starting to slide sideways, turn downhill. This
should help straighten out the vehicle and prevent the side slipping.
However, a much better way
to prevent this is to get out and “walk the
course”
so you know what the surface is like before you drive it.
some loose gravel and start to slide downhill. What should I do?
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Stalling on an Incline
If your vehicle stalls when you’re crossing an incline, be sure you (and your
passengers) get out on the uphill side, even
if the door there is harder to
open. If
you get out on the downhill side and the vehicle starts to roll over,
you’ll be right in its path.
If you have to walk
down the slope, stay
out
of the path the
vehicle will take if
it
does roll over.
Driving In Mud, Sand, Snow, Or Ice
When you drive in mud, snow or sand, your wheels won’t get good traction.
You can’t accelerate as quickly, turning
is more difficult, and you’ll need
longer braking distances.
It’s best to use
a low gear when you’re in mud - the deeper the mud, the
lower
the gear. In really deep mud, the idea is to keep your vehicle moving
so you don’t get stuck.
When you drive
on sand, you’ll sense a change in wheel traction. But it will
depend upon how loosely packed the sand is. On loosely packed sand
(as on
beaches or sand dunes) your tires
will tend to sink into the sand. This 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.
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