GMC SONOMA 2003 Owner's Manual

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.
{CAUTION:
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.
Q: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?
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.
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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.
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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.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.
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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
CAUTION: (Continued)
CAUTION: (Continued)
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 4-28for
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 are 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,
steering, suspension, wheels, tires and exhaust
system for damage. Also, check the fuel lines and
cooling system for any leakage.
Your vehicle will require more frequent service due to
off-road use. Refer to the Maintenance Schedule
for additional information.
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Driving at Night
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.
Here are some tips on night driving.
Drive defensively.
Don’t drink and drive.
Adjust your inside rearview mirror to reduce the
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.
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.
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.
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You can be temporarily blinded by approaching
headlamps. It can take a second or two, or even several
seconds, for your eyes to re-adjust 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 alm caused by dust. Dirty glass makes
lights dazzle andash 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
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.
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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.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 can’t, try to slow down before you
hit them.
{CAUTION:
Wet brakes can cause accidents.They won’t
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 your brake pedal lightly
until your brakes work normally.
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Hydroplaning
Hydroplaning is dangerous. So much water can build up
under your tires that they can actually ride on the
water. This can happen if the road is wet enough and
you’re going fast enough. When your vehicle is
hydroplaning, it has little or no contact with the road.
Hydroplaning doesn’t happen often. But it can if
your tires do not have much tread or if the pressure in
one or more is low. It can happen if a lot of water is
standing on the road. If you can see reections
from trees, telephone poles or other vehicles, and
raindrops“dimple”the water’s surface, there could be
hydroplaning.
Hydroplaning usually happens at higher speeds.
There just isn’t a hard and fast rule about hydroplaning.
The best advice is to slow down when it is raining.
Driving Through Deep Standing Water
Notice:If you drive too quickly through deep
puddles or standing water, water can come in
through your engine’s air intake and badly damage
your engine.Never drive through water that is
slightly lower than the underbody of your vehicle.
If you can’t avoid deep puddles or standing
water, drive through them very slowly.
Driving Through Flowing Water
{CAUTION:
Flowing or rushing water creates strong forces.
If you try to drive through flowing water, as you
might at a low water crossing, your vehicle can
be carried away.As little as six inches of
flowing water can carry away a smaller vehicle.
If this happens, you and other vehicle
occupants could drown.Don’t ignore police
warning signs, and otherwise be very cautious
about trying to drive through flowing water.
Some Other Rainy Weather Tips
Besides slowing down, allow some extra following
distance. And be especially careful when you
pass another vehicle. Allow yourself more clear
room ahead, and be prepared to have your
view restricted by road spray.
Have good tires with proper tread depth.
SeeTires on page 5-58.
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City Driving
One of the biggest problems with city streets is the
amount of traffic on them. You’ll want to watch out for
what the other drivers are doing and pay attention
to traffic signals.Here are ways to increase your safety in city driving:
Know the best way to get to where you are
going. Get a city map and plan your trip into
an unknown part of the city just as you would for a
cross-country trip.
Try to use the freeways that rim and crisscross
most large cities. You’ll save time and energy.
SeeFreeway Driving on page 4-32.
Treat a green light as a warning signal. A traffic
light is there because the corner is busy enough
to need it. When a light turns green, and just before
you start to move, check both ways for vehicles
that have not cleared the intersection or may
be running the red light.
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Freeway Driving
Mile for mile, freeways (also called thruways, parkways,
expressways, turnpikes or superhighways) are the
safest of all roads. But they have their own special rules.The most important advice on freeway driving is:
Keep up with traffic and keep to the right. Drive at the
same speed most of the other drivers are driving.
Too-fast or too-slow driving breaks a smooth trafficow.
Treat the left lane on a freeway as a passing lane.
At the entrance, there is usually a ramp that leads to the
freeway. If you have a clear view of the freeway as you
drive along the entrance ramp, you should begin to check
traffic. Try to determine where you expect to blend with
theow. Try to merge into the gap at close to the
prevailing speed. Switch on your turn signal, check your
mirrors and glance over your shoulder as often as
necessary. Try to blend smoothly with the trafficow.
Once you are on the freeway, adjust your speed to the
posted limit or to the prevailing rate if it’s slower.
Stay in the right lane unless you want to pass.
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 isn’t another vehicle in
your“blind”spot.
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