1997 CHEVROLET SUBURBAN heating

Heating Ventilation System
The heater works best if you keep your windows closed
while using it. On cold days, use the HEATER or
VENT/HEAT setting with the temperature knob in
the
red area.
If you use the engine coolant heater before starting your
engine in cold weather,
20°F (-8 O C) or lower, your
heating system will produce warmer air faster, to heat
the passenger compartment in cold weather.
The use
of an engine coolant heater also reduces the
time it takes for the engine to reach normal operating
temperature, and shortens the time it takes the heater to
reach full output. For more information, see “Engine
Coolant Heater” in the Index. For
mild outside temperatures when little heating or
cooling is needed, use VENT to direct outside air
through your vehicle. Air will flow through the
instrument panel outlets.
Your vehicle’s ventilation system supplies outside air
to the inside of your vehicle when it is moving. With
the side windows closed, air will flow into the front
air inlet grilles, through the vehicle, and out the air
exhaust valves.
Outside air will also enter the vehicle when the heater or
the air conditioning fan
is running, unless you have the
recirculation button pushed
in. For more information on
the recirculation button, see
“Air Conditioning” earlier
in this section.
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Ventilation Tips
Your vehicle has air outlets in the center and on the sides
of your instrument panel. You can move the outlets from
side to side or up and down to direct the flow of air, or
close the outlets altogether. When you close
an outlet, it
will increase the flow
of air coming out of any outlets
that are open. These outlets do not completely shut off
airflow when in a closed vent position.
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Keep the hood and front air inlet free of ice, snow or
any other obstruction (such as leaves). The heater
and defroster will work far better, reducing the
chance
of fogging the inside of your windows.
When you enter a vehicle in cold weather, turn the
blower fan to
HI for a few moments before driving.
This helps clear the intake ducts
of snow and
moisture, and reduces the chance
of fogging the
inside
of your windows.
Keep the air path under the front seats clear of
objects. This helps air to circulate throughout
your vehicle.
The use of hood air deflectors may adversely
affect the performance of the heating and air
conditioning system.
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Trailer Brakes
If your trailer weighs more than 1,000 Ibs. (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.
Your trailer brake system can tap into the vehicle’s
hydraulic brake system only if:
The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.
0.02 cubic inch (0.3 cc) of fluid from your vehicle’s
master cylinder. Otherwise, both braking systems
won’t work well. You could even lose your brakes.
The trailer’s brake system will use less than
If everything checks out this far, make the brake tap at
the
port on the master cylinder that sends the 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
If you have a rear-most window open and you
pull
a trailer with your vehicle, carbon monoxide
(CO) could come into your vehicle.
You 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:
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Have your exhaust system inspected for
leaks, and make necessary repairs before
starting
on your trip.
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 the
recirculation button
or MAX because it
only recirculates the air inside your vehicle.
(See “Comfort Controls”
in the Index.)
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Making ’hms
NOTICE:
Making very sharp turns while trailering could
cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you’re turning with a trailer, make wider turns than
normal.
Do this so your trailer won’t strike soft shoulders,
curbs, road signs, trees or other objects. Avoid jerky or
sudden maneuvers. Signal well
in advance.
Turn Signals When Towing a Trailer
The arrows on your instrument panel will flash
whenever you signal a turn or lane change. Properly
hooked up, the trailer lamps will also flash, telling other
drivers you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel 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 around
45 mph (70 kmh) to reduce the
possibility of engine and transmission overheating.
If you have an automatic transmission, you can tow
in
AUTOMATIC OVERDRIVE (0). You may want to
shift the transmission to THIRD
(3) or, if necessary, a
lower gear selection if the transmission shifts too often
(e.g., under heavy loads and/or hilly conditions).
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a
lower temperature than at normal altitudes. If you turn
your engine off immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar
to engine overheating. To avoid this, let the
engine run while parked (preferably on level ground)
with the automatic transmission in PARK
(P) for a few
minutes before turning the engine off. If you do get the
overheat warning, see “Engine Overheating” in
the Index.
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Section 5 Problems On The Road
Here you’ll find what to do about some problems that can occur on the road.
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5-3
5-3
5-8
5-11 Hazard
Warning Flashers
Other Warning Devices
Jump Starting
Towing Your Vehicle
Engine Overheating (Gasoline Engines) Cooling System
-- Gasoline Engines
Engine Fan Noise
If a Tire Goes Flat
Changing
a Flat Tire
If You’re Stuck: In Sand, Mud, Ice or
Snow
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5-2 1
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5-22
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Engine Overheating
(Gasoline Engine)
You will find a coolant temperature gage on your
vehicle’s instrument panel.
If your vehicle has a diesel engine, see “Engine
Overheating” in the Diesel Engine Supplement.
If Steam Is Coming From Your Engine
Steam from an overheated engine can burn you
badly, even
if you just open the hood. Stay away
from the engine
if you see or hear steam coming
from it. Just turn it
off and get everyone away
from the vehicle until it cools down. Wait until
there is no sign of steam or coolant before you
open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch fire. You or
others could be badly burned. Stop your engine if
it overheats, and get out of the vehicle until the
engine
is cool.
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If your engine catches fire because you keep
driving with no coolant, your vehicle can be
badly damaged. The costly repairs would not be
covered by your warranty.
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If the differential is at operating temperature (warm),
add enough lubricant to raise the level
to the bottom of
the filler plug hole.
If the differential is cold, add enough lubricant
to raise
the level to
1/2 inch (12 mm) below the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind
of lubricant to use. See “Recommended Fluids and
Lubricants” in the Index.
Engine Coolant
The cooling system in your vehicle is filled with new
DEX-COOL@ engine coolant. This coolant is designed
to remain
in your vehicle for 5 years or 150,000 miles
(240
000 km), whichever occurs first, if you add only
DEX-COOL@ extended life coolant.
The following explains
your cooling system and how
to add coolant when it is low. If you have a problem
with engine overheating, see “Engine Overheating” in
the Index.
A 50/50 mixture of water and the proper coolant for
your vehicle will:
0 Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 “F ( 129 * C).
0 Protect against rust and corrosion.
0 Help keep the proper engine temperature.
0 Let the warning gages work as they should.
NOTICE:
When adding coolant, it is important that you use
only DEX-COOL@ (silicate-free) coolant.
If coolant other than DEX-COOL@ is added to
the system, premature engine, heater core or
radiator corrosion may result.
In addition, the
engine coolant will require change sooner
-- at
30,000 miles (50 000 km) or 24 months,
whichever occurs first. Damage caused by the use
of coolant other than DEX-COOL@ is not
covered by your new vehicle warranty.
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Radiator Pressure Cap
The radiator pressure cap must be tightly installed with
the arrows on the cap lined up with the overflow tube on
the radiator filler neck.
NOTICE:
Your radiator cap is a 15 psi (105 kPa)
pressure-type cap and must be tightly installed to
prevent coolant loss and possible engine damage
from overheating. Be sure the arrows on the cap
line up with the overflow tube on the radiator
filler neck.
Thermostat
Engine coolant temperature is controlled by a thermostat
in the engine coolant system. The thermostat stops the
flow
of coolant through the radiator until the coolant
reaches a preset temperature.
When you replace your thermostat, an
AC@ thermostat
is recommended.
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