service CHEVROLET BLAZER 2003 2.G Service Manual

What Kind of Engine Oil to Use
Oils recommended for your vehicle can be identi®ed by
looking for the starburst symbol.
This symbol indicates that
the oil has been certi®ed
by the American Petroleum
Institute (API). Do not
use any oil which does not
carry this starburst
symbol.
If you choose to perform the engine oil change service
yourself, be sure the oil you use 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 certi®ed for
gasoline engines.
You should also use the proper viscosity oil for your
vehicle, as shown in the viscosity chart.
5-13

As in the chart shown previously, SAE 5W-30 is the
only viscosity grade recommended for your vehicle. You
should look for and use only oils which have the API
Starburst symbol and which are also identi®ed as
SAE 5W-30. If you cannot ®nd such SAE 5W-30 oils,
you can use an SAE 10W-30 oil which has the API
Starburst symbol, if it's going to be 0ÉF (-18ÉC)
or above. Do not use other viscosity grade oils, such as
SAE 10W-40 or SAE 20W-50 under any conditions.
Notice:Use only engine oil with the American
Petroleum Institute Certi®ed For Gasoline Engines
starburst symbol. Failure to use the recommended
oil can result in engine damage not covered by
your warranty.
GM Goodwrench
žoil meets all the requirements for
your vehicle.
If you are in an area of extreme cold, where the
temperature falls below-20ÉF (-29ÉC), it is
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Don't add anything to your oil. The recommended oils
with the starburst symbol are all you will need for
good performance and engine protection.
When to Change Engine Oil
If any one of these is true for you, use the short trip/city
maintenance schedule:
·Most trips are less than 5 miles (8 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).
·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 ®lter
every 3,000 miles (5 000 km) or 3 months Ð whichever
occurs ®rst.
If none of them is true, use the long trip/highway
maintenance schedule. Change the oil and ®lter every
7,500 miles (12 500 km) or 12 months Ð whichever
occurs ®rst. Driving a vehicle with a fully warmed engine
under highway conditions will cause engine oil to
break down slower.
5-14

Remote Oil Filter (Four-Wheel Drive)
The access door for the
remote oil ®lter is in the
steering linkage shield
assembly located under
the radiator support.
Turn the screw to unlock
or lock the door. If you
open the door, make sure
it is securely closed
when you are ®nished.
What to Do with Used Oil
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 dispose of clothing or
rags containing used engine oil. See the manufacturer's
warnings about the use and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from the
®lter before disposal. Never dispose of oil by putting it
in the trash, pouring it on the ground, into sewers, or intostreams 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.
Engine Air Cleaner/Filter
SeeEngine Compartment Overview on page 5-10for
more information on the location of the engine air
cleaner/®lter.
5-15

Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmission ¯uid
level is when the engine oil is changed.
Change both the ¯uid and ®lter 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
regularly reaches 90ÉF (32ÉC) or higher.
·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 ¯uid and ®lter every 50,000 miles
(83 000 km).
See
Part A: Scheduled Maintenance Services on
page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership 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 ¯uid can damage
your transmission. Too much can mean that some
of the ¯uid could come out and fall on hot engine
part or exhaust system parts, starting a ®re.
Too little ¯uid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission ¯uid.
Wait at least 30 minutes before checking the
transmission ¯uid level if you have been driving:
·When outside temperatures are above 90ÉF (32ÉC).
·At high speed for quite a while.
·In heavy traffic Ð especially in hot weather.
·While pulling a trailer.
To get the right reading, the ¯uid should be at normal
operating temperature, which is 180ÉF to 200ÉF
(82ÉC to 93ÉC).
5-17

Manual Transmission Fluid
When to Check
A good time to have it checked is when the engine oil is
changed. However, the ¯uid in your manual transmission
doesn't require changing.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at your GM dealership
service department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading.
Notice:Too much or too little ¯uid can damage
your transmission. Too much can mean that some
of the ¯uid could come out and fall on hot engine
part or exhaust system parts, starting a ®re.
Too little ¯uid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission ¯uid.
Check the ¯uid level only when your engine is off, the
vehicle is parked on a level place and the transmission
is cool enough for you to rest your ®ngers on the
transmission case.Then, follow these steps:
1. Remove the ®ller plug.
2. Check that the lubricant level is up to the bottom of
the ®ller plug hole.
3. If the ¯uid level is good, install the plug and be sure
it is fully seated. If the ¯uid level is low, add more
¯uid as described in the next steps.
5-20

How to Add Fluid
Here's how to add ¯uid. Refer to the Maintenance
Schedule to determine what kind of ¯uid to use. See
Part D: Recommended Fluids and Lubricants on
page 6-33.
1. Remove the ®ller plug.
2. Add ¯uid at the ®ller plug hole. Add only enough
¯uid to bring the ¯uid level up to the bottom of the
®ller plug hole.
3. Install the ®ller plug. Be sure the plug is fully
seated.
Hydraulic Clutch
The hydraulic clutch linkage in your vehicle is
self-adjusting. The clutch master cylinder reservoir is
®lled with hydraulic clutch ¯uid.
It is not necessary to regularly check clutch ¯uid unless
you suspect there is a leak in the system. Adding
¯uid won't correct a leak.
A ¯uid loss in this system could indicate a problem.
Have the system inspected and repaired.
When to Check and What to Use
Refer to the Maintenance Schedule to determine how
often you should check the ¯uid level in your clutch
master cylinder reservoir and for the proper ¯uid. See
Part B: Owner Checks and Services on page 6-26andPart D: Recommended Fluids and Lubricants on
page 6-33.
5-21

If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL
while stopped. If it is safe to do so, pull off the
road, shift to PARK (P) or NEUTRAL and let the
engine idle.
2. Turn on your heater to full hot at the highest fan
speed and open the window as necessary.
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning doesn't come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there's still no sign of steam, idle the engine for three
minutes while you're parked. Push down the accelerator
until the engine speed is about twice as fast as
normal idle speed for at least three minutes while you're
parked. If you still have the warning,
turn off the
engine and get everyone out of the vehicleuntil it
cools down.
You may decide not to lift the hood but to get service
help right away.
Cooling System
When you decide it's safe to lift the hood, here's what
you'll see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Cooling Fan
If the coolant inside the coolant recovery tank is boiling,
don't do anything else until it cools down. The vehicle
should be parked on a level surface.
5-27

When the engine is cold, the coolant level should be at
least up to the ADD mark. If it isn't, you may have a
leak at the pressure cap or in the radiator hoses, heater
hoses, radiator, water pump or somewhere else in
the cooling system.
{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Don't touch them. If you
do, you can be burned.
Don't run the engine if there is a leak. If you
run the engine, it could lose all coolant. That
could cause an engine ®re, and you could be
burned. Get any leak ®xed before you drive the
vehicle.
If there seems to be no leak, start the engine again.
The engine cooling fan speed should increase when idle
speed is doubled by pushing the accelerator pedal
down. If it doesn't, your vehicle needs service. Turn off
the engine.
Notice:Engine damage from running your engine
without coolant isn't covered by your warranty.
5-28

Brake Wear
If you have four-wheel drive, your vehicle has four-wheel
disc brakes. If not, your vehicle has front disc brakes
and rear drum brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched warning sound when the brake pads
are worn and new pads are needed. The sound
may come and go or be heard all the time your vehicle
is moving (except when you are pushing on the
brake pedal ®rmly).
{CAUTION:
The brake wear warning sound means that
soon your brakes won't work well. That could
lead to an accident. When you hear the brake
wear warning sound, have your vehicle
serviced.
Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates may cause a brake
squeal when the brakes are ®rst applied or lightly
applied. This does not mean something is wrong with
your brakes.Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to GM torque speci®cations.
If you have rear drum brakes, they don't have wear
indicators, but if you ever hear a rear brake rubbing
noise, have the rear brake linings inspected immediately.
Also, the rear brake drums should be removed and
inspected each time the tires are removed for rotation or
changing. When you have the front brake pads
replaced, have the rear brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
See
Brake System Inspection on page 6-32.
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in
pedal travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
If you don't have four-wheel drive and your brake pedal
goes down farther than normal, your rear drum
brakes may need adjustment. Adjust them by backing
up and ®rmly applying the brakes a few times.
5-39

11. Try to start the vehicle that had the dead battery. If
it won't start after a few tries, it probably needs
service.
Notice:Damage to your vehicle may result from
electrical shorting if jumper cables are removed
incorrectly. To prevent electrical shorting, take care
that the cables don't touch each other or any
other metal. The repairs wouldn't be covered by
your warranty.
A. Heavy, Unpainted Metal Engine Part
B. Good Battery
C. Dead BatteryTo disconnect the jumper cables from both vehicles, do
the following:
1. Disconnect the black negative (-) cable from the
vehicle that had the dead battery.
2. Disconnect the black negative (-) cable from the
vehicle with the good battery.
3. Disconnect the red positive (+) cable from the
vehicle with the good battery.
4. Disconnect the red positive (+) cable from the other
vehicle.
5-44