wheel GMC SIERRA 1998 Service Manual

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 Push the brake pedal to stop the vehicle and keep it
from rolling backwards.
Also, apply the parking brake.
0 If your engine is still running, shift the transmission
to REVERSE (R), release the parking brake, and
slowly back down the hill in REVERSE (R).
0 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
PARK
(P) (or, shift to NEUTRAL (N) if your
vehicle has a manual transmission) and restart the
engine. Then, shift to REVERSE (R), release the
parking brake, and slowly back down the hill as
straight as possible in REVERSE (R).
0 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
must not do if you stall, or are
about to stall, when going up a hill.
0 Never attempt to prevent a stall by shifting into
NEUTRAL (N) (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 to
REVERSE (R), 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.
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@ 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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I-
I A CAUTION:
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~ 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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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 oe wed 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:
0 Windshield Washer Fluid: Is the reservoir full? Are
all windows clean inside and outside?
Wiper Blades: Are they in good shape?
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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?
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 n second, and you could crash and be injured.
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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. What’s the worst time
for this? “Wet ice.” Very cold
snow or ice can be slick and hard to drive
on. But wet
ice can be even more trouble because it may offer the
least traction of all. You
can get wet ice when it’s about
freezing
(32°F; 0°C) and freezing rain begins to fall.
Try to avoid driving
on wet ice until salt and sand crews
can get there.
Whatever
the condition -- smooth ice, packed, blowing
or loose snow
-- drive with caution.
Accelerate gently. Try not to break the fragile traction. If
you accelerate too fast, the drive wheels will spin and
polish the surface under the tires even more.
Your anti-lock brakes improve your vehicle’s stability
when
you make a hard stop on a slippery road. Even
though you have
an anti-lock braking system, you’ll
want to begin stopping sooner than you would on dry
pavement. See “Anti-Lock‘’ in the Index.
Allow greater following distance on any
slippery road.
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Recreational Vehicle Towing
There may be times when you want to tow your vehicle
behind another vehicle for use at your destination. Be
sure to use the proper towing equipment designed for
recreational vehicle towing. Follow the instructions for
the towing equipment.
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Two-Wheel-Drive Vehicles
Two-wheel-drive vehicles should not be towed with
all four wheels on the ground. Two-wheel drive
transmissions have no provisions for internal lubrication
while being towed. To properly tow these vehicles, they
should be placed on a platform trailer with all four
wheels off the ground.
In
rare cases when it's unavoidable that a
two-wheel-drive vehicle is to be towed with all 'four
wheels on the ground, the propeller shaft to axle yoke
orientation should be marked and the propeller shaft
removed following the applicable service manual
removal/installation procedure.
Dust or dirt can enter the back of the transmission
through the opening created by removing the propeller
shaft if proper protection is not provided. Also, check
the transmission fluid level before driving the truck.
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