2003 CHEVROLET AVALANCHE check engine

A 50/50 mixture of clean, drinkable water and
DEX-COOLžcoolant will:
·Give freezing protection down to-34ÉF (-37ÉC).
·Give boiling protection up to 265ÉF (129ÉC).
·Protect against rust and corrosion.
·Help keep the proper engine temperature.
·Let the warning lights and gages work as they
should.
Notice:When adding coolant, it is important that
you use only DEX-COOLž(silicate-free) coolant.
If coolant other than DEX-COOLžis 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 ®rst.
Damage caused by the use of coolant other
than DEX-COOL
žis not covered by your new vehicle
warranty.
What to Use
Use a mixture of one-halfclean, drinkable waterand
one-half DEX-COOLžcoolant which won't damage
aluminum parts. If you use this coolant mixture,
you don't need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle's coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you wouldn't get the overheat warning.
Your engine could catch ®re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
žcoolant.
Notice:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost wouldn't be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core and
other parts.
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.
5-25

Checking Coolant
The coolant surge tank is
located in the engine
compartment on the
passenger's side of the
vehicle.
See
Engine Compartment Overview on page 5-12for
more information on location.
{CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. Never turn the surge tank pressure cap
Ð even a little Ð when the engine and radiator
are hot.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the FULL
COLD mark.
If the LOW COOLANT LEVEL message comes on and
stays on, it means you're low on engine coolant.
See ªLow Coolant Levelº under
DIC Warnings and
Messages on page 3-57.
Adding Coolant
If you need more coolant, add the proper DEX-COOLž
coolant mixtureat the surge tank, but only when the
engine is cool.
5-26

How to Add Coolant to the Coolant
Surge Tank
If you haven't found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the coolant level isn't at the FULL COLD mark, add a
50/50 mixture of
clean, drinkable waterand DEX-COOLž
coolant at the coolant surge tank, but be sure the
cooling system, including the coolant surge tank
pressure cap, is cool before you do it. See
Engine
Coolant on page 5-24for more information.
If no coolant is visible in the surge tank, add coolant as
follows:
{CAUTION:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They
are under pressure, and if you turn the radiator
pressure cap -- even a little -- they can come
out at high speed. Never turn the cap when the
cooling system, including the radiator pressure
cap, is hot. Wait for the cooling system and
radiator pressure cap to cool if you ever have
to turn the pressure cap.
5-32

When to Check Power Steering Fluid
It is not necessary to regularly check power steering ¯uid
unless you suspect there is a leak in the system or
you hear an unusual noise. A ¯uid loss in this system
could indicate a problem. Have the system inspected
and repaired. See
Engine Compartment Overview
on page 5-12for reservoir location.
How to Check Power Steering Fluid
Turn the key off, let the engine compartment cool down,
wipe the cap and the top of the reservoir clean, then
unscrew the cap and wipe the dipstick with a clean rag.
Replace the cap and completely tighten it. Then
remove the cap again and look at the ¯uid level on the
dipstick.
The level should be at the FULL COLD mark. If
necessary, add only enough ¯uid to bring the level up to
the mark.
What to Use
To determine what kind of ¯uid to use, seePart D:
Recommended Fluids and Lubricants on page 6-17.
Always use the proper ¯uid. Failure to use the proper
¯uid can cause leaks and damage hoses and seals. All Other Engines
5-37

Brakes
Brake Fluid
Your brake master cylinder reservoir is ®lled with DOT-3
brake ¯uid. SeeEngine Compartment Overview on
page 5-12for the location of the reservoir.
There are only two reasons why the brake ¯uid level in
the reservoir might go down. The ®rst is that the
brake ¯uid goes down to an acceptable level during
normal brake lining wear. When new linings are put in,
the ¯uid level goes back up. The other reason is
that ¯uid is leaking out of the brake system. If it is, you
should have your brake system ®xed, since a leak
means that sooner or later your brakes won't work well,
or won't work at all.
So, it isn't a good idea to ªtop offº your brake ¯uid.
Adding brake ¯uid won't correct a leak. If you add ¯uid
when your linings are worn, then you'll have too
much ¯uid when you get new brake linings. You should
add (or remove) brake ¯uid, as necessary, only when
work is done on the brake hydraulic system.
{CAUTION:
If you have too much brake ¯uid, it can spill on
the engine. The ¯uid will burn if the engine is
hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake
¯uid only when work is done on the brake
hydraulic system. See ªChecking Brake Fluidº
in this section.
Refer to the Maintenance Schedule to determine when
to check your brake ¯uid. See
Part C: Periodic
MaintenanceInspections on page 6-15.
5-39

{CAUTION:
Using a match near a battery can cause battery
gas to explode. People have been hurt doing
this, and some have been blinded. Use a
¯ashlight if you need more light.
Be sure the battery has enough water. You
don't need to add water to the ACDelco
ž
battery installed in your new vehicle. But if a
battery has ®ller caps, be sure the right
amount of ¯uid is there. If it is low, add water
to take care of that ®rst. If you don't, explosive
gas could be present.
Battery ¯uid contains acid that can burn you.
Don't get it on you. If you accidentally get it in
your eyes or on your skin, ¯ush the place with
water and get medical help immediately.5. Check that the jumper cables don't have loose or
missing insulation. If they do, you could get a
shock. The vehicles could be damaged too.
Before you connect the cables, here are some
basic things you should know. Positive (+) will go to
positive (+) or to a remote positive terminal (+) if
the vehicle has one. Negative (-) will go to a heavy,
unpainted metal engine part or to a remote
negative (-) terminal, if the vehicle has one.
Don't connect positive (+) to negative (-) or you'll
get a short that would damage the battery and
maybe other parts too.
{CAUTION:
Fans or other moving engine parts can injure
you badly. Keep your hands away from moving
parts once the engine is running.
5-46

Vehicle Identi®cation
Vehicle Identi®cation Number (VIN)
This is the legal identi®er for your vehicle. It appears on
a plate in the front corner of the instrument panel, on
the driver's side. You can see it if you look through the
windshield from outside your vehicle. The VIN also
appears on the Vehicle Certi®cation and Service Parts
labels and the certi®cates of title and registration.
Engine Identi®cation
The 8th character in your VIN is the engine code. This
code will help you identify your engine, speci®cations
and replacement parts.
Service Parts Identi®cation Label
You'll ®nd this label located in the glove box. It's very
helpful if you ever need to order parts. On this label is:
·your VIN,
·the model designation,
·paint information and
·a list of all production options and special
equipment.
Be sure that this label is not removed from the vehicle.
Electrical System
Notice:Don't add anything electrical to your
vehicle unless you check with your dealer ®rst.
Some electrical equipment can damage your vehicle
and the damage wouldn't be covered by your
warranty. Some add-on electrical equipment can
keep other components from working as they
should.
Your vehicle has an air bag system. Before attempting
to add anything to your vehicle, see
Servicing Your
Air Bag-Equipped Vehicle on page 1-66.
5-96

Capacities and Speci®cations
Please refer toPart D: Recommended Fluids and Lubricants on page 6-17for more information. All capacities are
approximate.
Engine Speci®cations
Engine VIN Code Transmission Spark Plug Gap
VORTECŸ 5300 V8 T Automatic 0.060 INCHES (1.52 MM)
VORTECŸ 8100 V8 G Automatic 0.060 INCHES (1.52 MM)
Capacities and Speci®cations
ApplicationCapacities
English Metric
After re®ll, the level must be rechecked. See
Cooling System on page 5-30.
Engine Cooling System
VORTECŸ 5300 V8
VORTECŸ 8100 V816.5 quarts
24.0 quarts15.6 L
23.0 L
After re®ll, the level must be rechecked. Add enough engine oil so that the ¯uid is within the proper operating
range. See
Engine Oil on page 5-15.
5-106