brake GMC SONOMA 2004 Owner's Guide

Driving Downhill
When off-roading takes you downhill, you will want to
consider a number of things:
•How steep is the downhill? Will I be able to maintain
vehicle control?
•What is the surface like? Smooth? Rough?
Slippery? Hard-packed dirt? Gravel?
•Are there hidden surface obstacles? Ruts? Logs?
Boulders?
•What is 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 will not 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.
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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), or with the clutch pedal pressed
down in a manual shift. 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 is much more likely to happen going uphill. But if
it happens going downhill, here is what to do.
•Stop your vehicle by applying the regular brakes.
Apply the parking brake.
•Shift to PARK (P) (or to neutral 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.
•If the engine will not 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.
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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 is deep enough to cover your wheel hubs,
axles or exhaust pipe, do not try it — you probably will
not get through. Also, water that deep can damage
your axle and other vehicle parts.
If the water is not 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 will 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 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.
SeeDriving in Rain and on Wet Roads on page 4-29for
more information on driving through water.
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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.
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.
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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 not, try to slow down before you
hit them.
{CAUTION:
Wet brakes can cause accidents. They will 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 your brake pedal lightly
until your brakes work normally.
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Hill and Mountain Roads
Driving on steep hills or mountains is different from
driving in flat or rolling terrain.
If you drive regularly in steep country, or if you are
planning to visit there, here are some tips that can make
your trips safer and more enjoyable. SeeOff-Road
Driving with Your Four-Wheel-Drive Vehicle on
page 4-14for 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.
{CAUTION:
If you do not shift down, your brakes could get
so hot that they would not 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.
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{CAUTION:
Coasting downhill in NEUTRAL (N) or with the
ignition off is dangerous. Your brakes will have
to do all the work of slowing down. They could
get so hot that they would not 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.
•Stay in your own lane when driving on two-lane
roads in hills or mountains. Do not 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.
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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
will have a lot less traction or “grip” and will need to be
very careful.
What is 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 offerthe least traction of all. You can get wet ice when it is
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
will want to begin stopping sooner than you would on
dry pavement. SeeBraking on page 4-6.
•Allow greater following distance on any
slippery road.
•Watch for slippery spots. The road might be fine
until you hit a spot that is covered with ice. On
an otherwise clear road, ice patches may appear in
shaded areas where the sun can not 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 are actually on the ice, and avoid
sudden steering maneuvers.
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If your slide-in camper and its load weigh less than the
CWR, the center of gravity zone for your vehicle
may be larger.
Your dealer can help you make a good vehicle-camper
match. He’ll also help you determine your CWR.
Secure loose items to prevent weight shifts that could
affect the balance of your vehicle. When the truck
camper is loaded, drive to a scale and weigh on the
front and on the rear wheels separately to determine
axle loads. Individual axle loads should not exceed
either of the Gross Axle Weight Ratings (GAWR). The
total of the axle loads should not exceed the Gross
Vehicle weight Rating (GVWR). These ratings are given
on the vehicle certification label that is located on the
rear of the passenger’s door. If weight ratings are
exceeded, move or remove items to bring all weights
below the ratings.
If you want more information on curb weights, cargo
weights, cargo weight rating and the correct center
of gravity zone for your vehicle, your dealer can help
you. Just ask for a copy of “Consumer Information,
Truck-Camper Loading.”Trailer Recommendations
You must subtract your hitch load from the CWR for
your vehicle. Weigh your vehicle with your trailer
attached, so that you won’t go over the GVWR or the
GAWR.
You’ll get the best performance if you spread out the
weight of your load the right way, and if you choose the
correct hitch and trailer brakes.
For more information, seeTowing a Trailer on page 4-55
later in this section.
Pickup Conversion to Chassis Cab
General Motors is aware that some vehicle owners may
consider having the pickup box removed and a
commercial or recreational body installed. However, we
recommend that conversions of this type not be done
to pickups. Owners should be aware that, as
manufactured, there are differences between a chassis
cab and a pickup with the box removed which may
affect vehicle safety. For specific information on
this pickup, contact GM Customer Assistance. See
Customer Assistance Offices on page 7-4.
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Towing a Trailer
{CAUTION:
If you do not use the correct equipment and
drive properly, you can lose control when you
pull a trailer. For example, if the trailer is too
heavy, the brakes may not work well — or even
at all. You and your passengers could be
seriously injured. Pull a trailer only if you have
followed all the steps in this section. Ask your
dealer for advice and information about towing
a trailer with your vehicle.
Notice:Pulling a trailer improperly can damage
your vehicle and result in costly repairs that would
not be covered by your warranty. Always follow
the instructions in this section and check with your
dealer for more information about towing a trailer
with your vehicle.Your vehicle may be able to tow a trailer. To identify
what the vehicle trailering capacity is for your vehicle,
you should read the information in “Weight of the Trailer”
that appears later in this section.
If yours was built with trailering options, as many are,
it’s ready for heavier trailers. But trailering is different
than just driving your vehicle by itself. Trailering means
changes in handling, accelleration, braking, durability
and fuel economy. Successful, safe trailering takes
correct equipment, and it has to be used properly.
That’s the reason for this part. In it are many time-tested,
important trailering tips and safety rules. Many of
these are important for your safety and that of your
passengers. So please read this section carefully before
you pull a trailer.
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