2007 CHEVROLET AVALANCHE cooling

After Off-Road Driving
Remove any brush or debris that has collected
on the underbody, chassis, or under the hood.
These accumulations can be a re hazard.
After operation in mud or sand, have the brake
linings cleaned and checked. These substances
can cause glazing and uneven braking. Check the
body structure, steering, suspension, wheels,
tires, and exhaust system for damage. Also, check
the fuel lines and cooling system for any leakage.
Your vehicle will require more frequent service
due to off-road use. Refer to the Maintenance
Schedule for additional information.
Driving at Night
Night driving is more dangerous than day driving.
One reason is that some drivers are likely to
be impaired — by alcohol or drugs, with night
vision problems, or by fatigue.
Here are some tips on night driving.
Drive defensively.
Do not drink and drive.
Adjust the inside rearview mirror to reduce the
glare from headlamps behind you.
Since you cannot see as well, you may need
to slow down and keep more space between
you and other vehicles.
Slow down, especially on higher speed roads.
Your vehicle’s headlamps can light up only so
much road ahead.
In remote areas, watch for animals.
If you are tired, pull off the road in a safe
place and rest.
385

Hill and Mountain Roads
Driving on steep hills or mountains is different
from driving in at or rolling terrain.If you drive regularly in steep country, or if you are
planning to visit there, here are some tips that
can make your trips safer and more enjoyable.
SeeOff-Road Driving on page 368for information
about driving off-road.
Keep your vehicle in good shape. Check
all uid levels and also the brakes, tires,
cooling system, and transmission. These
parts can work hard on mountain roads.
{CAUTION:
If you do not shift down, the brakes could
get so hot that they would not work well.
You would then have poor braking or
even none going down a hill. You could
crash. Shift down to let the engine assist
the brakes on a steep downhill slope.
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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 uid (don’t overll), engine
oil, axle lubricant, belts, cooling system and
brake system. Each of these is covered in this
manual, and the Index will help you nd 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.
426

Service........................................................ 432
Accessories and Modications................... 433
California Proposition 65 Warning.............. 433
Doing Your Own Service Work.................. 434
Adding Equipment to the Outside
of Your Vehicle...................................... 435
Fuel............................................................. 435
Gasoline Octane........................................ 436
Gasoline Specications.............................. 436
California Fuel........................................... 436
Additives................................................... 437
Fuel E85 (85% Ethanol)............................ 438
Fuels in Foreign Countries........................ 439
Filling the Tank......................................... 440
Filling a Portable Fuel Container............... 442
Checking Things Under the Hood.............. 442
Hood Release........................................... 443
Engine Compartment Overview.................. 444
Engine Oil................................................. 446
Engine Oil Life System.............................. 449Engine Air Cleaner/Filter............................ 451
Automatic Transmission Fluid.................... 454
Engine Coolant.......................................... 457
Coolant Surge Tank Pressure Cap............ 460
Engine Overheating................................... 460
Overheated Engine Protection
Operating Mode..................................... 463
Cooling System......................................... 464
Engine Fan Noise..................................... 469
Power Steering Fluid ................................. 469
Windshield Washer Fluid........................... 470
Brakes...................................................... 472
Battery...................................................... 475
Jump Starting............................................ 476
Rear Axle.................................................... 482
Four-Wheel Drive........................................ 483
Front Axle................................................... 484
Headlamp Aiming........................................ 485
Section 5 Service and Appearance Care
429

A. Engine Air Cleaner/Filter. SeeEngine
Air Cleaner/Filter on page 451.
B. Air Filter Restriction Indicator (If Equipped).
SeeEngine Air Cleaner/Filter on page 451.
C. Coolant Surge Tank and Pressure Cap.
SeeCooling System on page 464and
Coolant Surge Tank Pressure Cap
on page 460.
D. Remote Positive (+) Terminal. See
Jump Starting on page 476.
E. Battery. SeeBattery on page 475.
F. Engine Oil Fill Cap. See “When to Add
Engine Oil” underEngine Oil on page 446.
G. Automatic Transmission Dipstick.
See “Checking the Fluid Level” under
Automatic Transmission Fluid on page 454.H. Remote Negative (−) Terminal (Out of View).
SeeJump Starting on page 476.
I. Engine Oil Dipstick (Out of View). See
“Checking Engine Oil” underEngine Oil
on page 446.
J. Engine Cooling Fan. SeeCooling System
on page 464.
K. Power Steering Fluid Reservoir. See
Power Steering Fluid on page 469.
L. Brake Master Cylinder Reservoir. See
“Brake Fluid” underBrakes on page 472.
M. Underhood Fuse Block. SeeUnderhood
Fuse Block on page 551.
N. Windshield Washer Fluid Reservoir.
See “Adding Washer Fluid” under
Windshield Washer Fluid on page 470.
445

Consistency of Readings
Always check the uid level at least twice using
the procedure described previously. Consistency
(repeatable readings) is important to maintaining
proper uid level. If readings are still inconsistent,
contact your dealer.
How to Add Automatic
Transmission Fluid
Refer to the Maintenance Schedule to determine
what kind of transmission uid to use. See
Recommended Fluids and Lubricants on page 574.
Using a funnel, add uid down the transmission
dipstick tube only after checking the transmission
uid while it is hot. A cold check is used only
as a reference. If the uid level is low, add only
enough of the proper uid to bring the level up to
the HOT area for a hot check. It does not take
much uid, generally less than one pint (0.5 L).
Do not overll.Notice:Use of the incorrect automatic
transmission uid may damage your vehicle,
and the damages may not be covered by
your warranty. Always use the automatic
transmission uid listed inRecommended
Fluids and Lubricants on page 574.
After adding uid, recheck the uid level as
described under “How to Check Automatic
Transmission Fluid,” earlier in this section.
When the correct uid level is obtained, push
the dipstick back in all the way; then ip the
handle down to lock the dipstick in place.
Engine Coolant
If your vehicle has the DURAMAX®Diesel engine,
see the DURAMAX®Diesel manual for more
information.
The cooling system in your vehicle is lled with
DEX-COOL
®engine coolant. This coolant is
designed to remain in your vehicle for ve years or
150,000 miles (240 000 km), whichever occurs rst,
if you add only DEX-COOL
®extended life coolant.
457

The following explains your cooling system and
how to add coolant when it is low. If you have
a problem with engine overheating, seeEngine
Overheating on page 460.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
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
the rst maintenance service after each
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.
What to Use
Use a mixture of one-half clean, drinkable water
and one-half DEX-COOL®coolant which will
not damage aluminum parts. If you use this coolant
mixture, you do not 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 would
not 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
®coolant.
458

Notice:If you use an improper coolant
mixture, your engine could overheat and be
badly damaged. The repair cost would not 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 extra inhibitors and/or
additives in your vehicle’s cooling system,
you could damage your vehicle. Use only
the proper mixture of the engine coolant
listed in this manual for the cooling system.
SeeRecommended Fluids and Lubricants
on page 574for more information.
Checking Coolant
The coolant surge tank is located in the engine
compartment on the passenger’s side of the
vehicle. SeeEngine Compartment Overview
on page 444for 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 — even a little — 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 your vehicle is equipped with a low coolant
sensor and the LOW COOLANT LEVEL message
comes on and stays on, it means you are low
on engine coolant. See “LOW COOLANT LEVEL”
underDIC Warnings and Messages on page 267.
459