2003 GMC SIERRA DENALI tires

be crushed or ki 1. 1 rays c_ out on L--,
uphill (high9 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 will improve traction. 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.
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 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.
,41so, water that deep can damage your
axle and other vehicle parts.
4-27

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
+- stop.
,,jving thr,,gh 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
water.
~ vehicle over. Don’t drive through rushing
I
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,
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.
See
Driving in Rain and on Wet Roads on page 4-30 for
more information on driving through water.
4-28

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
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
reflexes are tuned for driving on dry pavement.
4-30

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 reflections
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 Flowhg W=+er
--m
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
Turn on your low-beam headlamps - not just your
parking lamps
- to help make you more visible to
others.
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. See
Tires
on page 5-6 I.
4-33

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 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 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:
e
e e
e
e
e
e
Windshield Washer Fluid: Is the reservior 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 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?
4-35

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 a second, and you could crash and
be injured.
What can you do about highway hypnosis? First, be
aware that it can happen.
Then here are some tips:
Make sure your vehicle is well ventilated, with a
Keep your eyes moving. Scan the road ahead and
comfortably cool interior.
to the
sides. Check your mirrors and your
instruments frequently.
If you get sleepy, pull off the road into a rest,
service or parking area and take a nap, get some
exercise, or both. For safety, treat drowsiness
on the highway as an emergency.
Hill and Mountain Roads
Driving on steep hills or mountains is different from
driving in flat
or rolling terrain.
4-36

If you drive regularly in steep country, or if you’re
planning to visit there, here are some tips that can make
your trips safer and more enjoyable. See
Operating
Your All-Wheel-Drive Vehicle
Off Paved Roads on
page
4-16 for information about driving off-road.
Keep your vehicle in good shape. Check all fluid
levels and also the brakes, tires, cooling system
and transmission. These parts can work hard
on mountain roads.
Know how to go down hills. The most important
thing to know is this: let your engine do some of
the slowing down. Shift to a lower gear when you go
down a steep or long hill.
If you don’t I R down, your -____ 3s COL- ge-
so hot that they wouldn’t work well. You would
then have poor braking or even none going
down a hill. You could crash. Shift down to let
your engine assist your brakes on a steep downhill slope. Coasting
UVwnlll..
..I NEUTRAL (N) G. .... h the
ignition
off is dangerous. Your brakes will have
to do all the work
of slowing down. They could
get
so hot that they wouldn’t work well. You
would then have poor braking or even none
going down a
hill. You could crash. Always
have your engine running and your vehicle in
gear when you go downhill.
Know how to go uphill. You may want to shift down to
a lower gear. The lower gears help cool your engine
and transmission, and you can climb the hill better.
roads in hills or mountains. Don’t swing wide or cut
across the center of the road. Drive at speeds that let
you stay in your own lane.
As you go over the top of a hill, be alert. There could
be something in your lane, like a stalled car or an
accident.
You may see highway signs on mountains that warn
of special problems. Examples are long grades,
passing or no-passing zones, a falling rocks area or
winding roads. Be alert to these and take appropriate
action.
Stay in your own lane when driving on two-lane
4-37

Driving on Snow or Ice
Most of the time, those places where your tires meet
the road probably have good traction. the
least traction of all. You can get wet ice when it’s
about freezing (32°F; OOC) and freezing rain begins
to fall. Try to avoid driving on wet ice until salt and sand
crews can get there.
However,
if there is snow or ice between your tires and Whatever the condition - smooth ice, packed, blowing
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. Accelerate gently. Try not to break the fragile traction.
If
or loose snow - drive with caution.
you accelerate too fast, the drive wheels will spin and
polish the surface under the tires even more.
m
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 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
Braking on page 4-6.
Allow greater following distance on any slippery
road.
0 Watch for slippery spots. The road might be fine
until you hit a spot that’s covered with ice. On
an otherwise clear road, ice patches may appear
in
shaded areas where the sun can’t reach: around
clumps
of trees, behind buildings or under bridges.
Sometimes the surface of a curve or an overpass
may remain icy when the surrounding roads
are clear.
If you see a patch of ice ahead of you,
brake before you are on it. Try not to brake
while you’re actually on the ice, and avoid sudden
steering maneuvers.
4-39