2003 GMC SIERRA stop start

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?
Does the travel take you uphill or downhill?
(There’s more discussion of these subjects later.)
Will you have to stop suddenly or change direction
quickly?
When you drive over obstacles or rough terrain, keep a
rm grip on the steering wheel. Ruts, troughs or
other surface features can jerk the wheel out of your
hands if you’re not prepared.
When you drive over bumps, rocks, or other obstacles,
your wheels can leave the ground. If this happens,
even with one or two wheels, you can’t control
the vehicle as well or at all.Because you will be on an unpaved surface, it’s
especially important to avoid sudden acceleration,
sudden turns or sudden braking.
In a way, off-road driving requires a different kind of
alertness from driving on paved roads and highways.
There are no road signs, posted speed limits or
signal lights. You have to use your own good judgment
about what is safe and what isn’t.
Drinking and driving can be very dangerous on any
road. And this is certainly true for off-road driving. At the
very time you need special alertness and driving
skills, your reexes, perceptions and judgment can be
affected by even a small amount of alcohol. You
could have a serious—or even fatal—accident if you
drink and drive or ride with a driver who has been
drinking. SeeDrunken Driving on page 4-2.
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Driving Uphill
Once you decide you can safely drive up the hill, you
need to take some special steps.
Use a low gear and get arm grip on the steering
wheel.
Get a smooth start up the hill and try to maintain
your speed. Don’t use more power than you
need, because you don’t want your wheels to start
spinning or sliding.
Try to drive straight up the hill if at all possible.
If the path twists and turns, you might want to
nd another route.
{CAUTION:
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 killed. When driving up
hills, always try to go straight up.
Ease up on your speed as you approach the top of
the hill.
Attach aag to the vehicle to make you more
visible to approaching traffic on trails or hills.
Sound the horn as you approach the top of the hill
to let opposing traffic know you’re there.
Use your headlamps even during the day. They
make you more visible to oncoming traffic.
{CAUTION:
Driving to the top (crest) of a hill at full speed
can cause an accident. There could be a
drop-off, embankment, cliff, or even another
vehicle. You could be seriously injured or
killed. As you near the top of a hill, slow down
and stay alert.
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 youshoulddo:
Push the brake pedal to stop the vehicle and keep
if from rolling backwards. Also, apply the parking
brake.
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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?
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.
{CAUTION:
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 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.
Never go downhill with the transmission in
NEUTRAL (N). This is called“free-wheeling.”Your
brakes will have to do all the work and could
overheat and fade.
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 (P) 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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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.{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. Drive at a reduced speed and
avoid sharp turns or abrupt maneuvers.
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2003 - Sierra Denali

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.
{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.
Driving in Water
Heavy rain can meanashooding, andood 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, drive slowly through it.
At faster 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.
{CAUTION:
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.
SeeDriving in Rain and on Wet Roads on page 4-32for
more information on driving through water.
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2003 - Sierra Denali

Driving in Rain and on Wet Roads
Rain and wet roads can mean driving trouble. On a wet
road, you can’t stop, accelerate or turn as well
because your tire-to-road traction isn’t as good as on
dry roads. And, if your tires don’t have much tread left,
you’ll get even less traction. It’s always wise to go
slower and be cautious if rain starts to fall while you are
driving. The surface may get wet suddenly when your
reexes are tuned for driving on dry pavement.The heavier the rain, the harder it is to see. Even if your
windshield wiper blades are in good shape, a heavy
rain can make it harder to see road signs and
traffic signals, pavement markings, the edge of the road
and even people walking.
It’s wise to keep your wiping equipment in good shape
and keep your windshield washer tanklled with
washeruid. Replace your windshield wiper inserts
when they show signs of streaking or missing areas on
the windshield, or when strips of rubber start to
separate from the inserts.
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Once you are moving on the freeway, make certain you
allow a reasonable following distance. Expect to
move slightly slower at night.
When you want to leave the freeway, move to the
proper lane well in advance. If you miss your exit, do
not, under any circumstances, stop and back up. Drive
on to the next exit.
The exit ramp can be curved, sometimes 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.
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 thatrst
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’llnd 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:
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?
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 inated 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?
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You can tow in DRIVE (D). You may want to shift
the transmission to THIRD (3) or, if necessary, a
lower gear selection if the transmission shifts
too often (e.g., under heavy loads and/or hilly
conditions).
Three important considerations have to do with weight:
the weight of the trailer,
the weight of the trailer tongue
and the weight on your vehicle’s tires.
Tow/Haul Mode
Tow/haul is a feature that assists when pulling a heavy
trailer or a large or heavy load. The purpose of the
tow/haul mode is to:
Reduce the frequency and improve the predictability
of transmission shifts when pulling a heavy trailer or
a large or heavy load.
Provide the same solid shift feel when pulling a
heavy trailer or a large or heavy load as when
the vehicle is unloaded.
Improve control of vehicle speed while requiring
less throttle pedal activity when pulling a heavy
trailer or a large or heavy load.
Your vehicle may be equipped with a switch at the end
of the shift lever which when pressed enables
tow/haul. When the switch is pressed, a light on theinstrument panel will illuminate to indicate that tow/haul
has been selected. Tow/haul may be turned off by
pressing the switch again, at which time the indicator
light on the instrument panel will turn off. The vehicle will
automatically turn off tow/haul every time it is started.
Tow/haul is designed to be most effective when the
vehicle and trailer combined weight is at least 75 percent
of the vehicle’s Gross Combined Weight Rating
(GCWR). See Weight of the Trailer later in this section.
Tow/haul is most useful under the following driving
conditions:
When pulling a heavy trailer or a large or heavy
load through rolling terrain.
When pulling a heavy trailer or a large or heavy
load in stop and go traffic.
When pulling a heavy trailer or a large or heavy
load in busy parking lots where improved low
speed control of the vehicle is desired.
Operating the vehicle in tow/haul when lightly loaded or
with no trailer at all will not cause damage. However,
there is no benet to the selection of tow/haul when the
vehicle is unloaded. Such a selection when unloaded
may result in unpleasant engine and transmission driving
characteristics and reduced fuel economy. Tow/haul
is recommended only when pulling a heavy trailer or a
large or heavy load.
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