1993 CHEVROLET SUBURBAN brakes

Hill and Mountain Roads
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AM470001
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’re planning to visit
there, here are some tips that can make your trips safer and more enjoyable.
(See “Off-Road” in the Index
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. Don’t make your brakes do it
all. Shift
to a lower gear when you go down a steep or long hill. That
way, you will slow down without excessive use of your brakes.
I
CAUT’oN
A If you don’t shift down, your brakes could get so hot that they
v- 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.
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Coasting downhill in N (Neutral) 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 wouldn’t work well. You could crash. Always
have your engine running and your vehicle in gear when you go
I
downhill.
e
e
e
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. Don’t swing wide or cut across the center
of the road. Drive
at speeds that let you stay in your own lane. That way, you won’t be
surprised by
a vehicle coming toward you in the same lane.
It takes longer to pass another vehicle when you’re going uphill. You’ll
want to leave extra room
to pass. If a vehicle is passing you and
doesn’t have enough
room, slow down to make it easier for the other
vehicle to get by.
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 fallin\
g rocks
area, or winding roads. Be alert
to these and take appropriate action.
Winter driving can present special problems. See “Winter Driv\
ing”
in the
Index.
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Your Driving and the Road
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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 the least traction of all.
You can get “wet ice” when it’s 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 ability to make a hard stop on \
a slippery
road. Even though you have the anti-lock braking system, you’\
ll want to begin
stopping sooner than you would on dry pavement. See “Anti-lo\
ck” in the
Index.
Allow greater following distances on any slippery road.
Watch for slippery spots. The road might be fine until you hi\
t 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 cl\
umps 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.
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Your Driving and the Road
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Run your engine only as long as you must. This saves fuel. When you run
the engine, make
it go a little faster than just idle. That is, push the
accelerator slightly. This uses
less fuel for the heat that you get and it keeps
the battery charged.
You will need a well-charged battery to restart the
vehicle, and possibly
for signaling later on with your headlights. Let the heater
run for awhile. Then,
shut the engine off and close the window almost all the
way to preserve the heat. Start the engine again and repeat this only when
you feel really uncomfortable from the cold. But do it as little as possible.
Preserve the fuel as long as you can. To help keep warm, you can get out
of the vehicle and do some fairly vigorous exercises every half hour or so
until help comes.
If You’re Stuck in Deep Snow
This manual explains how to get the vehicle out of deep snow without
damaging it. See “Rocking Your Vehicle” in the Index.
Towing a mailer
I A If you don’t 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.
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Your Driving and 0% Road
Will you have to make any holes in the body of your vehicle when you
install a trailer hitch?
If you do, then be sure to seal the holes later
when you remove the hitch.
If you don’t seal them, deadly carbon
monoxide
(CO) from your exhaust can get into your vehicle (see “Carbon
Monoxide” in the Index). Dirt and water can, too.
Safety Chains
You should always attach chains between your vehicle and your trail\
er. Cross
the safety chains under the tongue of the trailer
so that the tongue will not
drop to the road
if it becomes separated from the hitch. Instructions about
safety chains may be provided by the trailer manufacturer. Follow the
manufacturer’s recommendation
for attaching safety chains. Always leave just
enough slack
so you can turn with your rig. And, never allow safety chains to
drag on the ground.
Trailer Brakes
If your trailer weighs more than 1,000 pounds (450 kg) loaded, then it needs
its own brakes-and they must be adequate. Be sure
to read and follow the
instructions for the trailer brakes
so you’ll be able to install, adjust and
maintain them properly.
Don’t tap into your vehicle’s brake system if the trailer’s brake system will use
more than
0.02 cubic inch (0.3 cc) of fluid from your vehicles master cylinder.
If it does, both braking systems won’t work well. You could even lose your
brakes.
Will the trailer brake parts take 3,000 psi (20 650 kPa) of pressure? If
not, the trailer brake system must not be used with your vehi\
cle.
If everything checks out this far, then make the brake fluid tap at the
port on the master cylinder that sends fluid
to the rear brakes. But don’t
use copper tubing for this.
If you do, it will bend and finally break off.
Use steel brake tubing.
Driving with a Trailer
Towing a trailer requires a certain amount of experience. Before setting out
for the open road, you’ll want
to get to know your rig. Acquaint yourself with
the feel of handling and braking with the added weight of the trailer. And
always keep in mind that the vehicle you are driving is now a good deal
longer and not nearly
so responsive as your vehicle is by itself.
Before you start, check the trailer hitch and platform, safety \
chains, electrical
connector, lights, tires and mirror adjustment.
If the trailer has electric brakes,
start your vehicle and trailer moving and then apply the trail\
er brake controller
by hand to be sure the brakes are working. This lets vou check your
electrical connection at the same time.
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If you have a rear-most window open and you pull a trailer with \
your
can’t see or smell
CO. It can cause unconsciousness or death (See
“Engine Exhaust” in the Index).
To maximize your safety when towing
a trailer:
- vehicle, carbon monoxide (CO) could come into your vehicle. You
Have the exhaust system inspected for leaks and make
Keep the rear-most windows closed.
If exhaust does come into your vehicle through a window in the
rear or another opening, drive with your front, main heating or
cooling system
on and with the fan on any speed. This will
bring fresh, outside air into your vehicle.
Do not use RECIR
because it only recirculates the air inside your vehicle. See
“Comfort Controls” in the Index.
necessary repairs before starting on your trip.
During your trip, check occasionally to be sure that the load is secure, and
that the lights and any trailer brakes are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as you would when
driving your vehicle without a trailer. This can help you avoid situations that
require heavy braking and sudden turns.
Passing
You’ll need more passing distance up ahead when you’re towing a tr\
ailer.
And, because you’re
a good deal longer, you’ll need to go much farther
beyond the passed vehicle before you can return to your lane.
Backing Up
Hold the bottom of the steering wheel with one hand. Then, to move the
trailer left, just move your hand to the left.
To move the trailer to the right,
move your hand to the right. Always back up slowly and,
if possible, have
someone guide you.
Making Turns
When you’re turning with a trailer, make wider turns than n\
ormal. Do this so
your trailer wheels won’t strike soft shoulders, curbs, road signs, trees, or
other objects. Avoid jerky or sudden maneuvers. Signal well in advance.
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Your Driving and the Road
Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle has to have a different turn signal
flasher and extra wiring. The green arrows on your instrument \
panel will flash
whenever you signal a turn
or lane change. Properly hooked up, the trailer
lights will also flash, telling other drivers you’re about
to turn, change lanes,
or stop.
When towing a trailer, the green arrows on your instrument pan\
el will flash 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 gear before 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.
On
a long uphill grade, shift down and reduce your speed to 45 mph (70
kmlh) or less to reduce the possibility of engine and transmission overheating.
If you have an automatic transmission, you should use D (or, as you need to,
a lower gear) when towing a trailer. Operating your vehicle in D when towing
a trailer will minimize heat buildup and extend the
life of your transmission.
Or,
if you have a manual transmission with fifth gear and you are to\
wing a
trailer, it’s better not
to use fifth gear, just drive in fourth gear (or, as you
need to, a lower gear).
Parking on Hilk
You really should not park your rig on a hill. If something goes wrong, your
rig could start
to move. People can be injured and both your vehicle and the
trailer can be damaged.
But
if you ever have to park your rig on a hill, here’s how to do it:
1. Apply your regular brakes, but don’t shift into P (Park) yet, or into gear
for a manual transmission.
2. Have someone place chocks under the trailer wheels.
3, When the wheel chocks are in place, release the regular brakes\
until the
4. Reapply the regular brakes. Then apply your parking brake, and \
then
chocks absorb the load.
shift
to P (Park), or R (Reverse) for a manual transmission.
5. If you have a four-wheel-drive vehicle, be sure the transfer case \
is in
a
drive gear-not in
N (Neutral).
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. .
6. Release the regular brakes.
CAUTION
It can be dangerous to get out of your vehicle if the shift lever is no
fully in
P (Park) wi-. the parking brake firmly set. Your vehicle can
roll.
If you have left the engine running, the vehicle can move suddenl\
y.
You or others could be injured.
To be sure your vehicle won’t move,
when you’re on fairly level ground, use the steps that foll\
ow.
If you have four-wheel drive and your transfer case is in N (Neutral),
your vehicle will be free to
roll, even if your shift lever is in P (Park)
So, be sure the transfer case is in a drive gear-not in N (Neutral).
If you are parking on a hill, or if you’re pulling a trailer, also see
I “Parking On Hills” in the Index. I
When You Are Ready to Leave After Parking on a Hill
1. Apply your regular brakes and hold the pedal down while you:
Start your engine.
Shift into a gear; and
Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and stow the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re pulling a \
trailer. .See
the Maintenance Schedule for more on this. Things that are especially
important in trailer operation are automatic transmission fluid (don’t overfill),
engine oil, axle lubricant, belts, cooling system, and brake ad\
justment. Each
of these is covered in this manual, and the Index will help you find them
quickly.
If you’re trailering, it’s a good idea to review these sections before
you start your trip.
Check periodically to see that all hitch nuts and bolts are tight.
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