2007 GMC SIERRA stop start

Scanning the Terrain
Off-road driving can take you over many different
kinds of terrain. You need to be familiar with
the terrain and its many different features. Here
are some things to consider.
Surface Conditions:Off-roading can take you
over hard-packed dirt, gravel, rocks, grass, sand,
mud, snow, or ice. Each of these surfaces
affects the steering, acceleration, and braking of
your vehicle in different ways. Depending upon the
kind of surface you are on, you may experience
slipping, sliding, wheel spinning, delayed
acceleration, poor traction, and longer braking
distances.Surface Obstacles:Unseen or hidden obstacles
can be hazardous. A rock, log, hole, rut, or
bump can startle you if you are 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 is 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 are not
prepared.
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Q:What should I do if my vehicle stalls, or
is about to stall, and I cannot 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 is what youshoulddo:
Push the brake pedal to stop the vehicle
and keep it from rolling backwards. Also, apply
the parking brake.
If the engine is still running, shift the
transmission to REVERSE (R), release the
parking brake, and slowly back down the hill in
REVERSE (R).
If the engine has stopped running, you will
need to restart it. With the brake pedal
pressed and the parking brake still applied,
shift the transmission to PARK (P) 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).
As you are backing down the hill, put your left
hand on the steering wheel at the 12 o’clock
position. This way, you will be able to tell if the
wheels are straight and maneuver as you
back down. It is best that you back down the
hill with the 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 youmust notdo if you stall,
or are about to stall, when going up a hill.
Never attempt to prevent a stall by shifting
into NEUTRAL (N) to rev-up the engine
and regain forward momentum. This will not
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 is steep
enough to cause you to roll over if you turn
around. If you cannot make it up the hill, you
must back straight down the hill.
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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
is not too steep to drive down may be
too steep to drive across. You could roll over
if you do not drive straight down.
Never go downhill with the transmission in
NEUTRAL (N). This is called “free-wheeling.”
The brakes will have to do all the work
and could overheat and fade.
Q:Am I likely to stall when going downhill?
A:It is much more likely to happen going
uphill. But if it happens going downhill, here is
what to do.
1. Stop your vehicle by applying the regular
brakes. Apply the parking brake.
2. Shift to PARK (P) and, while still braking,
restart the engine.
3. Shift back to a low gear, release the parking
brake, and drive straight down.
4. If the engine will not start, get out and get help.
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Q:What if I am driving across an incline that
is not too steep, but I hit some loose
gravel and start to slide downhill. What
should I do?
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.
Stalling on an Incline
{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.If your vehicle stalls when you are crossing an
incline, be sure you, and any 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 will 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.
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Driving in Water
{CAUTION:
Driving through rushing water can be
dangerous. Deep water can sweep your
vehicle downstream and you and your
passengers could drown. If it is only
shallow water, it can still wash away the
ground from under your tires, and you
could lose traction and roll the vehicle
over. Do not drive through rushing water.
Heavy rain can mean ash ooding, and ood
waters demand extreme caution.
Find out how deep the water is before you drive
through it. If it is deep enough to cover the wheel
hubs, axles, or exhaust pipe, do not try it — you
probably will not get through. Also, water that deep
can damage the axle and other vehicle parts.If the water is not too deep, drive slowly through it.
At faster speeds, water splashes on the ignition
system and your vehicle can stall. Stalling can also
occur if you get the tailpipe under water. And,
as long as the tailpipe is under water, you
will never be able to start the engine. When you
go through water, remember that when the brakes
get wet, it may take you longer to stop.
SeeDriving in Rain and on Wet Roads on
page 408for more information on driving through
water.
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And, if your tires do not have much tread left, you
will get even less traction. It is 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. If your vehicle has four-wheel
drive, seeFour-Wheel Drive on page 147for
transfer case mode selection.
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 is wise to keep your wiping equipment in
good shape and keep your windshield washer uid
reservoir lled with washer uid. 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.
{CAUTION:
Wet brakes can cause accidents. They
may not work as well in a quick stop and
may cause pulling to one side. You could
lose control of the vehicle.
After driving through a large puddle of
water or a car wash, apply the brake pedal
lightly until the brakes work normally.
Driving too fast through large water puddles or
even going through some car washes can cause
problems, too. The water may affect your
brakes. Try to avoid puddles. But if you cannot, try
to slow down before you hit them.
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Before changing lanes, check your mirrors. Then
use your turn signal.
Just before you leave the lane, glance quickly
over your shoulder to make sure there is not
another vehicle in your blind spot.
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 are ready. Try to be well rested. If
you must start when you are not fresh — such
as after a day’s work — do not plan to make too
many miles that rst 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 is ready to go. If it
needs service, have it done before starting out. Of
course, you will nd experienced and able
service experts in GM dealerships all across North
America. They will be ready and willing to help
if you need it.
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Turn Signals When Towing a Trailer
The arrows on your instrument panel will
ash whenever you signal a turn or lane change.
Properly hooked up, the trailer lamps will also
ash, telling other drivers you’re about to
turn, change lanes or stop.
When towing a trailer, the arrows on your
instrument panel will ash for turns even if the
bulbs on the trailer are burned out. Thus, you may
think drivers behind you are seeing your signal
when they are not. It’s important to check
occasionally to be sure the trailer bulbs are still
working.
Driving On Grades
Reduce speed and shift to a lower gearbefore
you start down a long or steep downgrade. If you
don’t shift down, you might have to use your
brakes so much that they would get hot and no
longer work well.You can tow in DRIVE (D). You may want to shift
the transmission to lower gear selection if the
transmission shifts too often (e.g., under heavy
loads and/or hilly conditions).
You may also want to activate the tow/haul mode
if the transmission shifts too often. SeeTow/Haul
Mode Light on page 266.
When towing at high elevation on steep uphill
grades, consider the following: Engine coolant at
higher elevations will boil at a lower temperature
than at or near sea level. If you turn your
engine off immediately after towing at high
elevation on steep uphill grades, your vehicle may
show signs similar to engine overheating. To
avoid this, let the engine run while parked,
preferably on level ground, with the transmission
in PARK (P) at least ve minutes before turning the
engine off. If you do get the overheat warning,
seeEngine Overheating on page 516.
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