engine CHEVROLET ASTRO 1996 Repair Manual

Checking Engine Oil
Pull out the dipstick and clean it with a paper towel or
cloth, then
push it back in all the way. Remove it again,
keeping the tip down, and check
the level.
When to Add Oil
If the oil is at or below the ADD line, then you’ll need
to add some oil. But
you must use the right kind. This
part explains what kind
of oil to use. For crankcase
Don’t add too much oil. If your engine has so
much oil that the oil level gets above the
cross-hatched area that shows the proper
operating range, your engine could
be damaged.
Just fill it enough to put the level somewhere in the
proper operating range. Push
the dipstick all the way
back
in when you’re through.
6-12

What Kind of Oil to Use
Oils recommended for your vehicle can be identified by
looking for the “Starburst” symbol. This symbol
indicates that the oil has been certified by the American
Petroleum Institute
(API). Do not use any oil which
does not carry this Starburst symbol.
If you change your own oil,
be sure you use oil that has
the Starburst symbol
on the
front
of the oil container. If
you have your oil changed
for you, be sure
the oil
put into your engine
is
American Petroleum
Institute certified for
gasoline engines.
You should also use the proper viscosity oil for your
vehicle,
as shown in the following chart:
RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
SAE VISCOSITY GRADE OIL
FOR THE EXPECTED TEMPERATURE RANGE.
HOT
WEATHER
+ 40-
+ 20 -
0-
t
I W
COLD
LOOK
FOR THIS
SYMBOL
SA€ SW-30 PREFERRED
WEATHER
DO NOT USE SAE 2DW-50 OR ANY OTHER
GRADE OIL NOT RECOMMENDED
6-13

As shown in the chart, SAE 5W-30 is best for your
vehicle. However,
you can use SAE 1OW-30 if it’s going
to be
0°F (- 18 “C) or above. These numbers on an oil
container show its viscosity,
or thickness. Do not use
other viscosity oils, such as
SAE 20W-50.
NOTICE:
Use only engine oil with the American Petroleum
Institute Certified For Gasoline Engines
“Starburst” symbol. Failure to use the
recommended oil can result in engine damage
not covered
by your warranty.
GM Goodwrench@ oil meets all the requirements for
your vehicle.
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:
0
0
e
e
e
Most trips are less than 5 to 10 miles (8 to 16 km).
This is particularly important when outside
temperatures are below freezing.
Most trips include extensive idling (such
as frequent
driving in stop-and-go traffic).
Most trips are through dusty areas.
You frequently tow a trailer or use a carrier on top
of
your vehicle.
The vehicle is used for delivery service, police, taxi
or other commercial application.
Driving under these conditions causes engine oil to
break down sooner. If any
one of these is true for your
vehicle, then
you need to change your oil and filter
every 3,000 miles
(5 000 km) or 3 months -- whichever
occurs first.
If
none of them is true, change the oil and filter every
7,500 miles (12 500 km) or 12 months -- whichever
occurs first. Driving a vehicle with
a fully warmed
engine under highway conditions causes engine oil to
break down slower.
6-14

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.)
Engine Cover
Removing the Engine Cover
1. Move both front seats as far back as they will go.
Used oil can be a real threat to the environment.
If you
change your own oil, be sure to drain all free-flowing
oil
from the filter before disposal. Don’t ever dispose of oil
by putting
it in the trash, pouring it on the ground, into
sewers, or into streams or bodies of water. Instead,
recycle
it by taking it to a place that collects used oil. If
you have a problem properly disposing of your used oil,
ask your dealer, a service station or a local recycling
center
for help.
2. Remove the instrument panel extension
by removing
the two nuts that secure it in place.
6-15

7. Remove the two bolts at the engine cover. The bolts
are not supposed to come
out of the cover, only from
the front
of the dash.
When removing the cover, be careful
not to damage
the instrument panel or the trim.
8. Grasp the bottom of the cover and slide it rearward.
Then,
lift it up and out of the vehicle.
I
I
6-18

Installing the Engine Cover
1. Lift the engine cover into the vehicle and slide it all
the way forward. Make sure the rubber seal is over
the latches.
2. Install the two bolts at the engine cover.
3. Put the heater duct over the engine cover studs. Push
up
on the duct gently until it snaps into place.
4. Reconnect the electrical connectors.
5. Install the engine cover extension by gently squeezing
the sides and sliding
it into place. Make sure all of the
fastener clips engage, and the extension fits properly
in place. Replace and tighten the two screws.
5. Install the two nuts to secure the extension in place.
Air Cleaner
"""""".
To remove the air filter, lift the hood, unsnap both clips
and remove the top. After changing the filter, snap both
clips
to secure the air cleaner. Be sure the air cleaner lid
is correctly positioned to seal
out dust and contaminants
that are harmful to your engine.
Make sure the fresh air hose
is still attached after the
filter change.
6-19

Refer to the Maintenance Schedule to determine when to
replace the air filter and the crankcase ventilation filter.
See “Scheduled
N ntenance Services” in the Index.
Operating th, mgine with the air cleaner off
can cause
you or others to be burned. The air
cleaner not only cleans the air, it stops flame if
the engine backfires. If it isn’t there, and the
engine backfires, you could be burned. Don’t
drive with it
off, and be careful working on the
engine with the
air cleaner off.
NOTICE:
If the air cleaner is off, a backfire can cause a
damaging engine fire. And, dirt can easily get
into your engine, which will damage it. Always
have the air cleaner in place when you’re driving.
Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmission fluid
level is when the engine oil is changed,
Change both the fluid and filter every
15,000 miles
(25 000 km) if the vehicle is mainly driven under one
or more of these conditions:
In heavy city traffic where the outside temperature
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery service.
If
you do not use your vehicle under any of these
conditions, change
the fluid and filter every
30,000 miles (50 000 km).
See “Scheduled Maintenance Services” in
the Index.
regularly reaches
90°F (32°C) or
higher.
6-20

How to Check
Because this operation can be a little difficult, you
may choose to have this done at your GM dealer
Service Department.
If you do it yourself,
be sure to follow all the instructions
here, or
you could get a false reading on the dipstick.
NOTICE:
Too much or too little fluid can damage your
transmission.
Too much can mean that some of
the fluid could come out and fall on hot engine
parts or exhaust system parts, starting a fire. Be
sure to get an accurate reading if you check your
transmission fluid.
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving:
0 When outside temperatures are above 90°F (32°C).
At high speed for quite a while.
0 In heavy traffic -- especially in hot weather.
0 While pulling a trailer.
To get the right reading, the fluid should be at normal
operating temperature, which is 180°F
to ,200"F
(82°C
to 93°C).
Checking Transmission Fluid Hot
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50°F
(10°C). If it's colder than 50°F (lO"C), drive the
vehicle in DRIVE
(D) until the engine temperature gage
moves and then remains steady for
10 minutes. Then
follow the hot check procedures.
6-21

Checking Transmission Fluid Cold
A cold check is made after the vehicle has been sitting
for eight hours
or more with the engine off and is used
only as a reference. Let the engine run at idle for five
minutes if outside temperatures are 50°F (10°C) or
more. If it's colder than
50°F ( 10°C), you may have
to idle the engine longer. Should the fluid level be low
during a cold check,
you must perform a hot check
before adding fluid.
This will give you a more accurate
reading
of the fluid level.
Checking the Fluid Hot or Cold
Park your vehicle on a level place. Keep the
With the parking brake applied, place the shift lever
engine
running.
in PARK (P).
With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, position the shift
lever in PARK
(P).
0 Let the engine run at idle for three minutes or more. Then, without shutting
off the engine, follow these steps:
1. Flip the handle up and then pull out the dipstick and
wipe
it with a clean rag or paper towel.
2. Push it back in all the way, wait three seconds and
then
pull it back out again.
6-22

What to Use Rear 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. Add enough lubricant
to raise the level to the bottom of the filler plug hole. 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 (orange-colored, silicate-free) engine
coolant. This coolant is designed to remain in your
vehicle for
5 years or 100,000 miles (166 000 km),
whichever occurs first.
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).
Give boiling protection up to 265 “F (1 29°C).
0 Protect against rust and corrosion.
Help keep the proper engine temperature.
0 Let the warning lights and gages work as
they should.
6-25