1998 GMC SIERRA Owners Manual

@ 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
PARK (P) (or the manual transmission in
FIRST (1)) 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 NEUTRAL (N) when you leave the vehicle.
Leave
it in some gear. Shifting the transfer case to NEUTRAL
(N) can
cause your vehicle to roll even if the transmission
is in PARK
(P) (or, if you have the manual
transmission, even if you’re in gear). This is
because the NEUTRAL
(N) position on the
transfer case overrides the transmission.
You or
someone else could be injured.
If you are going to
leave your vehicle, set the parking brake and
shift the transmission to PARK
(P) (or, put your
manual transmission in FIRST
(1)). But do not
shift the transfer case to the NEUTRAL (N)
position. Leave the transfer case in the
2 Wheel,
4 High or 4 Low position.
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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?
Are there hidden surfxe 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‘?
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.
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?
A: Yes! These are important because if you
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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.
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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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 parking brake.
Shift to PARK (Pj (or to NEUTRAL (Nj 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.
0 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:
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.
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.
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Stalling on an Incline
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.
A:
What if I’m driving across an incline that’s not
too steep, but
I hit some loose gravel and start to
slide downhill. What should
I do?
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.
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 parn
the vehicle will take if it does roll over.
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I-
I A CAUTION:
-
~ Getting out on the downhill (low) side of a vehicle
~ stopped across an incline is dangerous. If the
vehicle
rolls over, you could be crushed or killed.
Always get out on the uphill (high) side of the
~ vehicle and stay well clear of the rollover path.
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.
Hard packed snow and ice offer the worst tire traction.
On these surfaces, 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.
r A CAUTION:
Driving on frozen lakes, ponds or rivers can be
dangerous. 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 only.
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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 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.
See “Driving Through Water’’ in the Index for more
information on driving through 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,
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steering, suspension, wheels, tires ana exhaust system
for damage.
Also, check the fuel lines and cooling
system for any leakage. Night driving is more dangerous than
day driving. One
reason is that some drivers are likely to
be impaired -- by
alcohol or
drugs, with night vision problems, or by fatigue.
Your vehicle will require more frequent service due to
off-road use. Refer
to the Maintenance Schedule for
additional information.
Driving at Night
Here are some tips on night driving.
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Drive defensively.
Don’t drink and drive.
Adjust your inside rearview mirror
to reauce me
glare from headlamps behind you.
Since you can’t see as well,
you may need to
slow down and keep more space between you and
other vehicles.
Slow down, especially on higher speed roads. Your
headlamps can light
up only so much road ahead.
In remote areas, watch for animals.
If you’re tired, pull off
the road in a safe place
and rest.
Night Vision
No one can see as well at night as in the daytime. But as
we get older
these differences increase. A 50-year-old
driver may require at least twice as much light
to see the
same thing at night as a 20-year-old.
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What you do in the daytime can also affect your night
vision. For example, if you spend the day in bright
sunshine you are wise to wear sunglasses. Your eyes will
have less trouble adjusting to night. But if you’re
driving, don’t wear sunglasses
at night. They may cut
down
on glare from headlamps, but they also make a lot
of things invisible.
You can be temporarily blinded by approaching
headlamps.
It can take a second or two, or even several
seconds, for your eyes to readjust to the dark. When you
are faced with severe glare (as from a driver who
doesn’t lower the high beams, or a vehicle with
misaimed headlamps), slow down a little. Avoid staring
directly into the approaching headlamps.
Keep your windshield and all the glass on your vehicle
clean
-- inside and out. Glare at night is made much
worse by dirt on the glass. Even the inside
of the glass
can build up a film caused
by dust. Dirty glass makes
lights dazzle and flash more than clean glass would,
making the pupils of your eyes contract repeatedly. Remember that your headlamps light up
far less
of a
roadway when you are in a turn or curve. Keep your
eyes moving; that way, it’s easier to pick
out dimly
lighted objects. Just as your headlamps should
be
checked regularly for proper aim, so should your eyes
be examined regularly. Some drivers suffer from night
blindness
-- the inability to see in dim light -- and aren’t
even aware of
it.
Driving in Rain and on Wet Roads
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