2004 CHEVROLET SILVERADO overheating

When to Check and What to Use
The clutch master cylinder
reservoir is located in the
rear of the engine
compartment on the
driver’s side of the vehicle.
SeeEngine Compartment
Overview on page 5-14
for more information
on location.
Refer to the Maintenance Schedule to determine how
often you should check the uid level in your clutch
master cylinder reservoir and for the proper uid. See
Owner Checks and Services on page 6-9and
Recommended Fluids and Lubricants on page 6-13.
How to Check and Add Fluid
The proper uid should be added if the level does not
reach the bottom of the diaphragm when it’s in place in
the reservoir. See the instructions on the reservoir cap.
Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs rst, if you add only
DEX-COOL
®extended life coolant.
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 5-38.
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 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.
5-35

Coolant Surge Tank Pressure Cap
SeeEngine Compartment
Overview on page 5-14
for more information
on location.
The coolant surge tank pressure cap must be fully
installed on the coolant surge tank.
Notice:If the pressure cap is not tightly
installed, coolant loss and possible engine
damage may occur. Be sure the cap is properly
and tightly secured.
Engine Overheating
You will nd a coolant temperature gage on your
vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 3-46. In addition, you will
nd a ENGINE OVERHEATED and a REDUCED
ENGINE POWER message in the Driver Information
Center on the instrument panel. SeeDriver Information
Center (DIC) on page 3-53.
Overheated Engine Protection
Operating Mode (V8 Engines Only)
If an overheated engine condition exists and the
REDUCED ENGINE POWER 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 5-20.
5-38

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. Just turn it off and get everyone away
CAUTION: (Continued)
CAUTION: (Continued)
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 your 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.
See “Overheated Engine Protection Operating
Mode” underEngine Overheating on page 5-38
for 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. See “Overheated Engine Protection
Operating Mode” underEngine Overheating on
page 5-38for information on driving to a safe place in
an emergency.
5-39

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. SeeLoading Your
Vehicle on page 4-56.
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.
20-Inch Tires
If your vehicle has the optional 20-inch P275/55R20
size tires, they are classied as touring tires and
are designed for on road use. The low-prole, wide
tread design is not recommended for “off-road” driving
or commercial uses such as snow plowing. See
Off-Road Driving on page 4-21andAdding a Snow
Plow or Similar Equipment on page 4-63for
additional information.
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.
5-74

E
Easy Exit Seat...............................................2-72
Electrical System
Add-On Equipment.....................................5-123
Fuses and Circuit Breakers.........................5-123
Power Windows and Other Power Options.......5-123
Windshield Wiper Fuses.............................5-123
Electronic Transfer Case..................................2-44
Emissions Inspection and Maintenance
Programs...................................................3-50
Engine
Air Cleaner/Filter.........................................5-25
Battery.......................................................5-52
Check and Service Engine Soon Light............3-48
Coolant......................................................5-35
Coolant Heater............................................2-26
Coolant Temperature Gage...........................3-46
Drive Belt Routing.......................................6-18
Engine Compartment Overview......................5-14
Exhaust.....................................................2-53
Fan Noise..................................................5-46
Oil .............................................................5-20
Overheating................................................5-38
Starting......................................................2-24
ENGINE COOLANT HOT.................................3-66
Engine Hour Meter Display...............................3-35
Engine Oil Additives........................................5-23
ENGINE OVERHEATED..................................3-66Entry Lighting.................................................3-18
Environmental Concerns..................................4-25
Event Data Recorders (EDR)............................. 7-9
Exit Lighting...................................................3-18
Express Down Windows..................................2-18
Extended Cab........................................1-56, 2-14
Extended Cab and Crew Cab...........................1-53
Extender, Safety Belt.......................................1-31
Exterior Lamps...............................................3-13
F
Fifth Wheel and Gooseneck Trailering................4-89
Filter
Engine Air Cleaner......................................5-25
Finding a Program Type (PTY) Station
(RDS and XM™).......................3-79, 3-90, 3-104
Finding a Station..................3-74, 3-77, 3-88, 3-102
Finish Care..................................................5-118
Finish Damage.............................................5-120
Five-Speed (VORTEC™ 4300 V6 and
4800 V8 Engines)........................................2-32
Five-Speed (VORTEC™ 6000 V8 Engine)...........2-31
Fixed Mast Antenna.......................................3-130
Flash-to-Pass................................................... 3-9
Flat Tire........................................................5-92
Flat Tire, Changing.........................................5-93
6