engine CHEVROLET SUBURBAN 1993 Service Manual

Hill and Mountain Roads
:.-. . , , . .;. . . . . . - ,. ..
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.
4-47
ProCarManuals.com

A
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.
4-48
ProCarManuals.com

t
If You’re Caught in a Blizzard
I-
.
If you are stopped by heavy snow, you could be in a serious situation. You
should probably stay with your vehicle unless you know for sure that you are
near help and you can hike through the snow, Here are
some things to do to
summon help and keep yourself and your passengers safe: Turn o\
n your
hazard flashers. Tie a red cloth to your vehicle
to alert police that you’ve
been stopped by the snow. Put on extra clothing or wrap
a blanket around
you.
If you have no blankets or extra clothing, make body insulators from
newspapers, burlap bags, rags, floor mats-anything you
can wrap around
yourself
or tuck under your clothing to keep warm.
You
can run the engine to keep warm, but be careful.
Snow can trap exhaust gases under your vehicle. This can cause\

deadly
CO (carbon monoxide) gas to get inside. CO could overcome
you and kill you. You can’t see
it or smell it, so you might not know
it is in your vehicle. Clear away
snow from around the base of your
vehicle, especially any that is blocking your exhaust pipe. And check
around again from time to time
to be sure snow doesn’t collect there.
Open
a window just a little on the side of the vehicle that’s away
I from the wind. This will help keep CO out.
4-55
ProCarManuals.com

Your Driving and the Road
AN480044
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.
4-56
ProCarManuals.com

I NOTICE
’
I advice in this section.
Wing a trailer improperly can damage your vehicle and result in costly
epairs not covered by your warranty. To pull a trailer correctly, follow the
Every vehicle is ready for some trailer towing,
If it 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,
durability, and fuel economy. Successful, safe trailering takes \
correct equipment, and it has to be used properly.
That’s the reason for this section. 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.
If You Do Decide To Pull A Trailer
If you do, here are some important points.
e
e
There are many different laws having to do with trailering. Make sure
your rig
will be legal, not only where you live but also where you’ll be\

driving.
A good source for this information can be state or provincial
police.
Consider using sway control with a utility model
if your trailer will weigh
3,000 pounds (1361 kg) or less, or with a wagon model if your trailer
will weigh
4,000 pounds (1800 kg) or less. You should always use sway
control with a utility model
if your trailer will weigh more than 3,000
pounds (1 361 kg), or with a wagon model if your trailer will weigh more
than
4,000 pounds (1800 kg). You can ask a hitch dealer about sway
controls.
Don’t tow a trailer at all during the first
500 miles (800 km) your new
vehicle is driven. Your engine, axle, or other parts could be damaged.
Then, during the first
500 miles (800 km) that you tow a trailer, don’t
drive over
50 mph (80 kmlh) and don’t make starts at full throttle. That
will help your engine and other parts
of your vehicle wear in at the
heavier loads.
4-57
ProCarManuals.com

I
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.
4-61
ProCarManuals.com

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).
4-62
ProCarManuals.com

. .
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.
4-63
ProCarManuals.com

Here you’ll find what to do about some problems that can occur on the road.
Hazard Warning Flashers ........................................................................\
............. 5-2
Other Warning Devices ........................................................................\
................. 5-3
Jump Starting ........................................................................\
................................ 5-3
Towing Your Vehicle, ........................................................................\
..................... 5-7
Engine Overheating ........................................................................\
....................... 5-8
Engine Fan Noise ........................................................................\
....................... 5-1 6
If a Tire Goes Flat ........................................................................\
...................... 5-16
Changing a Flat
Storing the Jack
If You’re Stuck: In
Tire ........................................................................\
............... 5-16
and
Tire. ........................................................................\
...... 5-30
Sand, Mud, Ice or Snow ................................................... 5-31
5-1
ProCarManuals.com

(-) or a metal engine part. Don’t connect (t) to (-) or you’ll get a
short that would damage the battery and maybe other parts, too.
A Fans or other moving engine parts can injure you badly. Keep your
h hands away from moving parts once the engines are running.
6. Connect the red positive (t) cable to the positive (t) terminal of the
vehicle with the dead battery. Use a remote positive
(+) terminal if the
vehicle has one.
Dead Baffery Good Battery
1
7. Don’t let the other end touch metal. Connect it to the positive (+)
terminal of the good battery. Use a remote positive (+) terminal if the
vehicle has one.
8.
Now connect the black negative (-) cable to the good battery’s negative
(-) terminal.
Don’t let the other end touch anything until the next step. The other end
of the negative cable
doesn’t go to the dead battery. It goes to a heavy
unpainted metal part on the engine
of the vehicle with the dead battery.
9. Attach the cable at least 18 inches (45 cm) away from the dead battery,
but not near engine
parts that move. The electrical connection is just as
good there, but the chance
of sparks getting back to the battery is much
less.
5-5
ProCarManuals.com