service CHEVROLET TRAIL BLAZER 2004 1.G Repair Manual

Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent engine and fuel system deposits from forming,
allowing your emission control system to work
properly. You should not have to add anything to your
fuel. However, some gasolines contain only the
minimum amount of additive required to meet U.S.
Environmental Protection Agency regulations. General
Motors recommends that you buy gasolines that
are advertised to help keep fuel injectors and intake
valves clean. If your vehicle experiences problems due
to dirty injectors or valves, try a different brand of
gasoline.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available in
your area to contribute to clean air. General Motors
recommends that you use these gasolines, particularly if
they comply with the specications described earlier.
Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not be covered under
your warranty.Some gasolines that are not reformulated for
low emissions may contain an octane-enhancing
additive called methylcyclopentadienyl manganese
tricarbonyl (MMT); ask the attendant where you
buy gasoline whether the fuel contains MMT. General
Motors does not recommend the use of such gasolines.
Fuels containing MMT can reduce the life of spark
plugs and the performance of the emission control
system may be affected. The malfunction indicator lamp
may turn on. If this occurs, return to your authorized
GM dealer for service.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel may be hard
to nd. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not
be covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you will be driving.
5-6

How to Reset the CHANGE ENGINE OIL
Light
The GM Oil Life System calculates when to change
your engine oil and lter based on vehicle use. Anytime
your oil is changed, reset the system so it can
calculate when the next oil change is required. If a
situation occurs where you change your oil prior to a
CHANGE ENGINE OIL light being turned on, reset the
system.
To reset the CHANGE ENGINE OIL light, do the
following:
1. Turn the ignition key to RUN with the engine off.
2. Fully press and release the accelerator pedal slowly
three times within ve seconds.
3. Turn the key to LOCK.
If the CHANGE ENGINE OIL light comes back on when
you start your vehicle, the engine oil life system has
not reset. Repeat the procedure.
For vehicles with the Driver Information Center, see
Driver Information Center (DIC) on page 3-48to reset
the system.
What to Do with Used Oil
Used engine oil contains certain elements that may be
unhealthy for your skin and could even cause cancer.
Do not 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 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.
5-19

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 50,000 miles
(83 000 km) if the vehicle is mainly driven under one or
more of these conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) 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
100,000 miles (166 000 km).
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 90°F (32°C).
At high speed for quite a while.
In heavy traffic-especially in hot weather.
While pulling a trailer.
To get the right reading, the uid should be at
normal operating temperature, which is 180°F to 200°F
(82°C to 93°C).
5-21

If No Steam Is Coming From Your
Engine
If you get an engine overheat warning but see or hear
no steam, the problem may not be too serious.
Sometimes the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer.
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 (N) 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 and you have not stopped, pull
over, stop, and park your vehicle right away.
If there’s still no sign of steam, you can 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.
5-27

The coolant level should
be at least up to the FULL
COLD 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. Do not touch them. If
you do, you can be burned.
Do not 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 is not covered by your warranty.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-29

Brake Wear
Your vehicle has four-wheel disc 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 will not 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 specications.
Brake linings should always be replaced as complete
axle sets.
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.
5-39

8. Now connect the black
negative (−) cable to
the negative (−)
terminal of the good
battery. Use a remote
negative (−) terminal
if the vehicle has one.
Don’t let the other end touch anything until the next
step. The other end of the negative (−) cable
doesn’tgo to the dead battery. It goes to a heavy,
unpainted metal engine part or to the remote
negative (−) terminal on the vehicle with the dead
battery. In the L6 engine, the remote negative (−)
terminal is located on the front engine lift bracket
and is marked GND. In the V8 engine, the
remote negative (–) terminal is located on the
accessory drive bracket and is marked GND.9. Connect the other end of the negative (−) cable to
the remote negative (−) terminal on the vehicle with
the dead battery.
10. Now start the vehicle with the good battery and run
the engine for a while.
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:If the jumper cables are removed in the
wrong order, electrical shorting may occur and
damage the vehicle. The repairs would not be
covered by your warranty. Remove the jumper
cables in the correct order, making sure that the
cables do not touch each other or other metal.
L6 EngineV8 Engine
5-44

Tires
Your new vehicle comes with high-quality tires made by
a leading tire manufacturer. If you ever have questions
about your tire warranty and where to obtain service,
see your GM Warranty booklet for details. For additional
information refer to the tire manufacturer’s booklet
included with your vehicle’s Owner’s Manual.
{CAUTION:
Poorly maintained and improperly used tires
are dangerous.
Overloading your tires can cause
overheating as a result of too much
friction. You could have an air-out and a
serious accident. See “Loading Your
Vehicle” in the Index.
Underinated tires pose the same danger
as overloaded tires. The resulting accident
could cause serious injury. Check all tires
frequently to maintain the recommended
pressure. Tire pressure should be checked
when your tires are cold.
CAUTION: (Continued)
CAUTION: (Continued)

Overinated tires are more likely to be
cut, punctured or broken by a sudden
impact — such as when you hit a pothole.
Keep tires at the recommended pressure.
Worn, old tires can cause accidents. If
your tread is badly worn, or if your tires
have been damaged, replace them.
Tire Sidewall Labeling
Useful information about a tire is molded into the
sidewall. The following illustrations are examples of a
typical P-Metric and a LT-Metric tire sidewall.
5-52

(A) Tire Size Code:The tire size code is a combination
of letters and numbers used to dene a particular
tire’s width, height, aspect ratio, construction type and
service description. See the “Tire Size Code” illustration
later in this section for more detail.
(B) Tire Performance Criteria Specication (TPC
Spec):Original equipment tires designed to GM’s
specic tire performance criteria have a TPC
specication code molded onto the sidewall. GM’s TPC
specications meet or exceed all federal safety
guidelines.
(C) Department of Transportation (DOT):The
Department of Transportation (DOT) code indicates that
the tire is in compliance with the U.S. Department of
Transportation Motor Vehicle Safety Standards.
(D) Tire Identication Number (TIN):The letters and
numbers following DOT code are the Tire Identication
Number (TIN). The TIN shows the manufacturer
and plant code, tire size, and date the tire was
manufactured. The TIN is molded onto both sides of the
tire, although only one side may have the date of
manufacture.
P-Metric Tire
5-53

(A) Tire Size:The tire size code is a combination of
letters and numbers used to dene a particular
tire’s width, height, aspect ratio, construction type and
service description. See the “Tire Size” illustration
later in this section for more detail.
(B) Tire Performance Criteria Specication (TPC
Spec):Original equipment tires designed to GM’s
specic tire performance criteria have a TPC
specication code molded onto the sidewall. GM’s TPC
specications meet or exceed all federal safety
guidelines.
(C) Dual Tire Maximum Load:Maximum load that can
be carried and the maximum pressure needed to
support that load when used in a dual conguration. For
information on recommended tire pressure see
Ination - Tire Pressure on page 5-60andLoading Your
Vehicle on page 4-47.(D) Department of Transportation (DOT):The
Department of Transportation (DOT) code indicates that
the tire is in compliance with the U.S. Department of
Transportation Motor Vehicle Safety Standards.
(E) Tire Identication Number (TIN):The letters and
numbers following DOT code are the Tire Identication
Number (TIN). The TIN shows the manufacturer
and plant code, tire size, and date the tire was
manufactured. The TIN is molded onto both sides of the
tire, although only one side may have the date of
manufacture.
(F) Tire Ply Material:The type of cord and number of
plies in the sidewall and under the tread.
(G) Single Tire Maximum Load:Maximum load that
can be carried and the maximum pressure needed
to support that load when used as a single. For
information on recommended tire pressure see
Ination - Tire Pressure on page 5-60andLoading Your
Vehicle on page 4-47.
5-55