2008 CHEVROLET AVALANCHE open hood

If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can burn
you badly, even if you just open the hood. Stay
away from the engine if you see or hear steam
coming from it. Turn it off and get everyone
away from the vehicle until it cools down.
Wait until there is no sign of steam or coolant
before you open the hood.
If you keep driving when the vehicles engine is
overheated, the liquids in it can catch re. You
or others could be badly burned. Stop your
engine if it overheats, and get out of the
vehicle until the engine is cool.
SeeOverheated Engine Protection Operating
Mode on page 5-30for information on driving
to a safe place in an emergency.Notice:If your engine catches re because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not be
covered by your warranty. SeeOverheated Engine
Protection Operating Mode on page 5-30for
information on driving to a safe place in an
emergency.
If No Steam Is Coming From Your
Engine
The ENGINE OVERHEATED STOP ENGINE or the
ENGINE OVERHEATED IDLE ENGINE message, along
with a low coolant condition, can indicate a serious
problem.
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. SeeTowing a Trailer on page 4-47.
5-29

If you get the ENGINE OVERHEATED STOP ENGINE
or the ENGINE OVERHEATED IDLE ENGINE message
with no sign of steam, try this for a minute or so:
1. If the vehicle has an air conditioner and it is on,
turn it off.
2. Turn on the heater to the highest temperature and
at the highest fan speed and open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (NEUTRAL)
while stopped. If it is safe to do so, pull off the road,
shift to P (Park) or N (NEUTRAL) and let the
engine idle.
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle immediately.
If there is still no sign of steam and your vehicle has an
engine-driven cooling fan, push down the accelerator
until the engine speed is about twice as fast as normal
idle speed for at least ve minutes while parked.
If there is still no sign of steam and your vehicle has an
electric cooling fan, idle the engine for ve minutes
while parked.If you still have the warning, turn off the engine and get
everyone out of the vehicle until it cools down. Also,
see “Overheated Engine Protection Operating Mode”
later in this section.
You might decide not to lift the hood but to get service
help right away.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
ENGINE POWER IS REDUCED message is displayed,
an overheat protection mode which alternates ring
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. Driving
extended miles (km) and/or 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. SeeEngine Oil on page 5-15.
5-30

Notice:If you leave your radio or other accessories
on during the jump starting procedure, they could
be damaged. The repairs would not be covered
by your warranty. Always turn off your radio and
other accessories when jump starting your vehicle.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or the accessory power outlets. Turn off
the radio and all the lamps that are not needed.
This avoids sparks and helps save both batteries.
And it could save the radio!
4. Open the hood on the other vehicle and locate the
positive (+) and negative (−) terminal locations on
that vehicle.
Your vehicle has a remote positive (+) jump starting
terminal and a remote negative (−) jump starting
terminal. You should always use these remote
terminals instead of the terminals on the battery.
If the vehicle has a remote positive (+) terminal,
it is located under a red plastic cover at the positive
battery post. To uncover the remote positive (+)
terminal, open the red plastic cover.The remote negative (-) terminal is a stud located
on the right front of the engine, where the negative
battery cable attaches.
SeeEngine Compartment Overview on page 5-14
for more information on the location of the remote
positive (+) and remote negative (−) terminals.
5-43

To adjust the vertical aim:
1. Open the hood. SeeHood Release on page 5-12
for more information.
2. Locate the aim dot on the lens of the low-beam
headlamp.
3. Record the distance from the ground to the aim dot
on the low-beam headlamp.4. At a wall measure from the ground upward (A) to
the recorded distance from Step 3 and mark it.
5. Draw or tape a horizontal line (B) on the wall or at
surface the width of the vehicle at the height of the
mark in Step 4.
Notice:Do not cover a headlamp to improve beam
cut-off when aiming. Covering a headlamp may
cause excessive heat build-up which may cause
damage to the headlamp.
6. Turn on the low-beam headlamps and place a
piece of cardboard or equivalent in front of the
headlamp not being adjusted. This allows only the
beam of light from the headlamp being adjusted
to be seen on the at surface.
5-51

Parking Brake and Automatic
Transmission Park (P) Mechanism
Check
{CAUTION:
When you are doing this check, your vehicle
could begin to move. You or others could be
injured and property could be damaged. Make
sure there is room in front of your vehicle in
case it begins to roll. Be ready to apply the
regular brake at once should the vehicle begin
to move.Park on a fairly steep hill, with the vehicle facing
downhill. Keeping your foot on the regular brake,
set the parking brake.
To check the parking brake’s holding
ability: With the engine running and transmission
in NEUTRAL (N), slowly remove foot pressure from
the regular brake pedal. Do this until the vehicle is
held by the parking brake only.
To check the PARK (P) mechanism’s holding ability:
With the engine running, shift to PARK (P). Then
release the parking brake followed by the regular
brake.
Contact your dealer/retailer if service is required.
Hood Support Gas Strut Service
Visually inspect gas strut for signs of wear, corrosion,
cracks, loss of lubricant, or other damage. Check
the hold open ability of gas strut. If necessary, replace
with genuine parts from your dealer/retailer.
Underbody Flushing Service
At least every spring, use plain water to ush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.
6-12

G
Gage
Engine Coolant Temperature.........................3-42
Fuel..........................................................3-49
Oil Pressure...............................................3-46
Speedometer..............................................3-34
Tachometer.................................................3-34
Voltmeter Gage...........................................3-39
Garage Door Opener.......................................2-64
Gasoline
Octane........................................................ 5-5
Specications............................................... 5-6
Glove Box.....................................................2-71
GM Mobility Reimbursement Program.................. 7-6
H
Hazard Warning Flashers................................... 3-6
Head Restraints..............................................1-11
Headlamp
Aiming .......................................................5-50
Headlamps
Bulb Replacement.......................................5-53
Daytime Running Lamps...............................3-16
Exterior Lamps............................................3-14
Flash-to-Pass............................................... 3-9Headlamps (cont.)
Halogen Bulbs............................................5-53
High/Low Beam Changer................................ 3-9
On Reminder..............................................3-15
Heated Seats................................................... 1-5
Heater...........................................................3-21
Engine Coolant...........................................2-34
Heater...........................................................3-24
Highbeam On Light.........................................3-48
Highway Hypnosis...........................................4-29
Hill and Mountain Roads..................................4-30
Hood
Checking Things Under................................5-12
Release.....................................................5-12
Horn ............................................................... 3-6
How to Wear Safety Belts Properly...................1-19I
Ignition Positions.............................................2-30
Infants and Young Children, Restraints...............1-38
Ination - Tire Pressure...................................5-64
Instrument Panel
Brightness..................................................3-18
Cluster.......................................................3-33
Overview..................................................... 3-4
6