2002 CHEVROLET AVALANCHE service

4-70 When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:

start your engine,

shift into a gear, and

release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you're
pulling a trailer. See the Maintenance Schedule for
more on this. Things that are especially important
in trailer operation are automatic transmission fluid
(don't overfill), engine oil, axle lubricant, belt, cooling
system and brake system. Each of these is covered
in this manual, and the Index will help you find them
quickly. If you're trailering, it's a good idea to review
these sections before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.

4-72
Instrument Panel Jumper Wiring Harness
This harness is included with the heavy-duty trailer
wiring package. The harness is for an electric trailer
brake controller and includes a trailer battery feed fuse.
This harness and fuse should be installed by your dealer
or a qualified service center.Four
-Wire Trailer Harness Adapter
If you need to tow a
light
-duty trailer with a
standard four
-way round
pin connector, an adapter
is included.
Connect the adapter with the tab (arrow) pointing
towards the top. The cap on the wiring harness will lock
onto the tab (arrow) and help hold the adapter in place.

5-7
9. Connect the
other end of the
negative (
-) cable
at least 18 inches
(45 cm) away from
the dead battery, but
not near engine
parts that move.
The electrical connection is just as good there, and the
chance of sparks getting back to the battery is much less.10. Now start the vehicle with the good battery and run
the engine for awhile.
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 they don't touch each other or any
other metal. The repairs wouldn't be covered by
your warranty.

5-9
Towing Your Vehicle
Consult your dealer or a professional towing service
if you need to have your vehicle towed. See ªRoadside
Assistanceº and ªRecreational Vehicle Towingº in
the Index.
Engine Overheating
You will find a coolant temperature gage on your
vehicle's instrument panel. See ªEngine Coolant
Temperature Gageº in the Index. In addition,
you will find a LOW COOLANT, CHECK COOLANT
TEMP, ENGINE OVERHEATED and a REDUCED
ENGINE POWER message in the message center on the
instrument panel. See ªMessage Centerº in the Index.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
REDUCED ENGINE POWER message is displayed, an
overheat protection mode which alternates firing groups
of cylinders helps prevent engine damage. In this mode,
you will notice a loss in power and engine performance.
This operating mode allows your vehicle to be driven to
a safe place in an emergency. Towing a trailer in the
overheat protection mode should be avoided.
NOTICE:
After driving in the overheated engine protection
operating mode, to avoid engine damage, allow
the engine to cool before attempting any repair.
The engine oil will be severely degraded. Repair
the cause of coolant loss, change the oil and reset
the oil life system. See ªEngine Oilº in the Index.

5-11 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. See ªDriving on Gradesº in the Index.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. If your air conditioner is on, turn it off.
2. Turn on your heater to full hot at the highest fan
speed and open the window as necessary.
3. If you're in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving
-- DRIVE (D).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 vehicle until it cools down. Also, see
ªOverheated Engine Protection Operating Modeº listed
previously in this section.
You may decide not to lift the hood but to get service
help right away.

5-14
NOTICE:
When adding coolant, it is important that you
use only DEX
-COOL
(silicate-free) coolant.
If coolant other than DEX-COOL is 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 first. Damage caused by the
use of coolant other than DEX
-COOL
is not
covered by your new vehicle warranty.
If there seems to be no leak, start the engine again.
See if the engine cooling fan speed increases when idle
speed is doubled by pushing the accelerator pedal
down. If it doesn't, your vehicle needs service.
Turn off the engine.
How to Add Coolant to the Coolant
Surge Tank
If you haven't found a problem yet, but the coolant level
isn't at or above the FILL COLD mark, add a 50/50
mixture of clean, drinkable water and DEX
-COOL

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 ªEngine Coolantº in the Index
for more information.
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 coolant
surge tank pressure cap
-- even a little -- they
can come out at high speed. Never turn the cap
when the cooling system, including the coolant
surge tank pressure cap, is hot. Wait for
the cooling system and coolant surge tank
pressure cap to cool if you ever have to turn
the pressure cap.

6-
6-1
Section 6 Service and Appearance Care
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 part devoted to its appearance care.
6
-2 Service
6
-3 Fuel
6
-5 Fuels in Foreign Countries
6
-6 Filling Your Tank
6
-8 Checking Things Under the Hood
6
-12 Engine Oil
6
-18 Engine Air Cleaner/Filter
6
-20 Passenger Compartment Air Filter
6
-21 Automatic Transmission Fluid
6
-24 Rear Axle
6
-25 Four-Wheel Drive
6
-27 Engine Coolant
6
-30 Coolant Surge Tank Pressure Cap
6
-30 Power Steering Fluid
6
-32 Windshield Washer Fluid6
-33 Brakes
6
-37 Battery
6
-38 Bulb Replacement
6
-43 Windshield Wiper Blade Replacement
6
-44 Tires
6
-53 Appearance Care
6
-53 Cleaning the Inside of Your Vehicle
6
-57 Cleaning the Outside of Your Vehicle
6
-61 GM Vehicle Care/Appearance Materials
6
-62 Vehicle Identification Number (VIN)
6
-63 Electrical System
6
-71 Replacement Bulbs
6
-72 Capacities and Specifications
6
-73 Normal Maintenance Replacement Parts

6-2
Service
Your dealer knows your vehicle best and wants you to
be happy with it. We hope you'll go to your dealer for
all your service needs. You'll get genuine GM parts and
GM
-trained and supported service people.
We hope you'll want to keep your GM vehicle all GM.
Genuine GM parts have one of these marks:
Doing Your Own Service Work
If you want to do some of your own service work, you'll
want to use the proper service manual. It tells you much
more about how to service your vehicle than this manual
can. To order the proper service manual, see ªService
and Owner Publicationsº in the Index.
Your vehicle has an air bag system. Before attempting
to do your own service work, see ªServicing Your Air
Bag
-Equipped Vehicleº in the Index.
You should keep a record with all parts receipts and
list the mileage and the date of any service work you
perform. See ªMaintenance Recordº in the Index.