engine coolant CHEVROLET SUBURBAN 1994 Owner's Manual

Service & Appearance
I Section
Here you will find information about the care of your vehicle . This section
begins with service and fuel information. and then it shows how to check
important fluid and lubricant levels
. There is also technical information
about your vehicle. and a section devoted to its appearance care
.
Service ................................................... 6-3
Fuel (Gasoline Engines)
............................
Diesel Fuel Requirements and Fuel System ..........
Checking Things Under the Hood ........... .....
........ 6-4
.......... 6-5
......... 6-14
HoodRelease
.......................................... 6-14
Cleaning Your Diesel Engine
............................ 6-15
Engine Oil (Except Diesel)
................................ 6-16
Engine Oil (Diesel Engines)
............................... 6-22
Aircleaner
.................... .................. 6-27 ..
Automatic Transmission Fluid ............................. 6-28
Manual Transmission Fluid
............................... 6-31
Hydraulic Clutch
........................................ 6-32
RearAxle
............................................. 6-33
Transfer Case
.......................................... 6-34
FrontAxle
........................................... 6-35
Engine Coolant
......................................... 6-35
Power Steering Fluid
.............. .................. 640
Windshield Washer Fluid
............................... 6-42
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Engine Oil Additives
Don’t add anything to your oil. Your GM dealer is ready to advise if you
think something should be added.
When to Change Engine Oil
See if any one of these is true for you:
Most trips are less than 4 miles (6 km).
0 It’s below freezing outside and most trips are less than 10 miles (16 km).
The engine is at low speed most of the time (as in door-to-door
You tow a trailer often.
delivery,
or in stop-and-go traffic).
Most trips are through dusty places.
The vehicle is frequently operated off-road.
If any one
of these is true for your vehicle, then you need to change your oil
andfifilter every 3,000 miles (5 000 km) or 3 months - whichever comes
first
.
Light Duty Emissions:
If none of them is true, change the oil every 7,500 miles (12 500 km) or
12 months - whichever comes first. Change the filter at the first oil change
and at every other oil change after that.
Heavy Duty Emissions:
If none of them is true, change the oil every 6,000 miles ( 10 000 km) or
12 months - whichever comes first. Change the filter at the first oil change
and at every other oil change after that if mileage determines when you
change your oil.
If time determines when you change your oil, change the
filter each time you change your
oil.
Engine Coolant Heater (Engine Block Heater)
An engine coolant heater can be a big help if you have to park outside in
very cold weather,
0°F (-1 8 “C) or colder. If your vehicle has this option,
see “Engine Coolant Heater
” in the Index.
What to Do with Used Oil
Did you know that used engine oil contains certain elements that may be
unhealthy for your skin and could even cause cancer? Don’t let used oil stay
on your skin for very long. Clean your skin and nails with soap and water,
or
a good hand cleaner. Wash or properly throw away clothing or rags
containing
used engine oil. (See the manufacturer’s warnings about the use
and disposal of oil products.)
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Front Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how often to check the
lubricant and when to change
it. See “Scheduled Maintenance Services” in
the Index.
How to Check Lubricant
If the level is below
the bottom of the filler
plug hole, you’ll need
to add some lubricant.
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 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.
The proper coolant for your vehicle will:
Give freezing protection down to -20°F (-29”C), or -34°F (-37°C) in
Give boiling protection up to 258°F (1 25°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Canada
and for vehicles with the cold climate option.
Let the warning lights and gages work as they should.
6-35 ProCarManuals.com

What to Use
use a mixture of one-half clean water (preferably distilled) and one-half
antifreeze that meets
“GM Specification 6038-M,” which won’t damage
aluminum
parts. You can also use a recycled coolant conforming to “GM
Specification 6038-M” with a complete coolant flush and refill. If you use
this mixture, you don’t need
to add anything else.
NOTICE:
If you use an improper coolant mix, your engine could overheat
and be badly damaged. The repair cost wouldn’t be covered by
your warranty.
TOO much water in the mix can freeze and crack
the engine, radiator, heater core and other parts.
Some conditions, such as air trapped in the cooling system, can affect the
coolant level in the radiator. Check the coolant level when the engine is cold
and follow the steps under “Adding Coolant” for
the proper way to add
coolant.
If you have to add coolant more than four times a year, have your dealer
check your cooling system.
NOTICE:
If you use the proper coolant, you don’t have to add extra
inhibitors
or additives which claim to improve the system. These
can be harmful.
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Adding Coolant -Gas Engines
The coolant recovery
tank is located on the
passenger side at the
rear comer of the
engine compartment
To Check Coolant
When your engine is cold, the coolant level should be at COLD, or a little
higher. When your engine
is warm, the level should be up to HOT, or a little
higher.
To Add Coolant
If you need more coolant, add the proper mix at the coolant recovery tank.
Add coolant mix at the recovery tank, but be careful not to spill it.
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Adding Coolant -Diesel Engines
.. The coolant surge tank
is located on the
passenger side at the
rear corner
of the
engine compartment
To Check Coolant
When your engine is cold, the coolant level should be at the COLD mark,
or
a little higher. When your engine is warm, the level should be above the
COLD mark.
If this light comes on,
it means you're low
on engine coolant.
To Add Coolant
If you need more coolant, add the proper mix ut the surge tank, but only
when the
engine is cool.
Open the bleed valve
on the thermostat housing to allow trapped air out of
the system. Close the bleed valve when coolant begins to flow out.
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Radiator Pressure Cap-Gas Engines
I I
The radiator pressure
cap must be tightly
installed with the
arrows on the cap
lined up with the
ovefflow 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.
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Surge Tank Pressure Cap- Diesel Engines
The surge tank
pressure cap must be
tightly installed with
the arrows
on the cap
lined up with the top
tube
of the coolant
surge tank.
NOTICE:
Your surge tank pressure cap 1s a unique 15 psi (105 kPa)
pressure-type cap for use with surge tank cooling systems only.
It 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 top tube
of the coolant surge tank.
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.
Power Steering Fluid
I NOTICE:
Always turn the engine off before checking or adding power
steering
fluid. The power steering pump cap is close to the fan
and other moving parts.
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LAMP OR BULB
INSTRUMENT
P ANEL
Transmission Indicator (PRNDL)
Daytime Running Lights Indicator?'
Charging System Indicator Lamp
Instrument Cluster Illumination -Gage
Cluster
Instrument Cluster Illumination
-Tachometer Cluster
Headlamp Beam Indicator
Directional Signal Indicator
Brake Warning Indicator
Safety Belt Warning
Check Gages Indicator Malfunction Indicator ("Service Engine
Soon") Lamp
Upshift Indicator
Glow Plugs Lamp*:"
Low Coolant Lamp**
Water
in Fuel Lamp**
Service Throttle
Soon Lamp**
'k*Diesel only
'fCanadian Vehicles only
TRADE NO.
161 74
74
194
194 74
74
74
74
74 74
74
74 74
74
74
6
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Explanation Of Scheduled Maintenance Services
Below are explanations of the services listed in the maintenance charts.
The proper fluids and lubricants to
use are listed in this section. Make sure
whoever services your vehicle uses these.
All parts should be replaced and
all necessary repairs done before you or anyone else drives the vehicle.
1. ENGINE OIL AND OIL FILTER CHANGE* -ALWAYS USE SH
ENERGY CONSERVIJTG TI (GASOLINE ENGINE) OR CF-4/SH
(DIESEL ENGINE) QUALITY OILS OF THE PROPER VISCOSITY.
To determine the preferred viscosity oil for your vehicle’s engine
(e.g.
SAE 5W-30 or low-30), see “Engine Oil” in the Index.
2. CHASSIS LUBRICATION - Lubricate the front suspension, king
pin bushings, steering linkage, transmission, and transfer case shift
linkage, parking brake cable guides, rear driveline center splines and
front axle propshaft splines, brake pedal springs, and clutch pedal
springs at the intervals specified.
Ball joints and king pin bushings should not be lubricated unless their
temperature is
10°F (-12”C), or higher. When the weather is cold, let
them warm up before lubrication or they could be damaged.
Also, be sure to check all the vehicle fluid levels at this time.
3. CLUTCH FORK BALL STUD LUBRICATION (5-SPEED
MANUAL TRANSMISSION
WITH DEEP LOW ) - Not
applicable to utility or wagon models.
4. COOLING SYSTEM SERVICE*? - Drain, flush and refill system
with new coolant. See “Engine Coolant’’
in the Index for the proper
coolant and mixture to use
in your vehicle.
Also inspect the hoses and replace them
if they are cracked, swollen, or
deteriorated. Tighten all
hose clamps (except constant tension clamps).
Remove debris and clean
the outside of the radiator and air
conditioning condenser. Wash the radiator
neck. To ensure proper
operation, pressure test the radiator and cap.
5. AIR CLEANER FILTER REPLACEMENT* - Replace at every
30,000 miles (50 000 km) or more often under dusty conditions. Ask
your dealer for the proper replacement intervals
for your driving
conditions.
6. FRONT WHEEL BEARING REPACK (2-WHEEL DRIVE
ONLY)
- Clean and repack the front wheel bearings at each brake
relining, or at the specified interval, whichever comes first.
4’ An Emission Control Service
*A fluid loss in these systems may indicate a problem. Have them
inspected and repaired at once.
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