2003 CHEVROLET SILVERADO coolant

Turn Signals When Towing a Trailer
The arrows on your instrument panel will ¯ash whenever
you signal a turn or lane change. Properly hooked up,
the trailer lamps will also ¯ash, telling other drivers
you're about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will ¯ash for turns even if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It's
important to check occasionally to be sure the trailer
bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you don't shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
If you have an automatic transmission, you can tow in
DRIVE (D). You may want to shift the transmission
to lower gear selection if the transmission shifts too often
(e.g., under heavy loads and/or hilly conditions).
You may also want to activate the tow/haul mode if the
transmission shifts too often. See
Tow/Haul Mode
Light on page 3-53.If you have a 5-speed manual transmission and you are
towing a trailer, it's better not to use FIFTH (5) gear.
Just drive in FOURTH (4) gear (or, as you need
to, a lower gear).
If you have a 6-speed manual transmission and you are
towing a trailer, it's better not to use SIXTH (6) gear.
Drive in FIFTH (5) gear (or, as you need to, a lower gear).
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal altitudes. If you turn your
engine off immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar to engine overheating. To avoid this, let the
engine run while parked (preferably on level ground)
with the automatic transmission in PARK (P) (or
the manual transmission out of gear and the parking
brake applied) for a few minutes before turning the
engine off. If you do get the overheat warning,
see
Engine Overheating on page 5-33.
4-87

Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside of Your
Vehicle......................................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-4
Gasoline Speci®cations....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-5
Fuels in Foreign Countries...............................5-6
Filling Your Tank............................................5-6
Filling a Portable Fuel Container.......................5-8
Checking Things Under
the Hood......................................................5-8
Hood Release................................................5-9
Engine Compartment Overview.......................5-10
Engine Oil...................................................5-16
Engine Air Cleaner/Filter................................5-21
Automatic Transmission Fluid (Except Allison
Transmission
ž) ..........................................5-23Automatic Transmission Fluid (Allison
Transmission
ž) ..........................................5-26
Manual Transmission Fluid.............................5-28
Hydraulic Clutch...........................................5-29
Engine Coolant.............................................5-30
Coolant Surge Tank Pressure Cap..................5-33
Engine Overheating.......................................5-33
Cooling System............................................5-36
Engine Fan Noise.........................................5-41
Power Steering Fluid.....................................5-42
Windshield Washer Fluid................................5-43
Brakes........................................................5-44
Battery........................................................5-47
Jump Starting...............................................5-48
All-Wheel Drive..............................................5-54
Rear Axle.......................................................5-55
Four-Wheel Drive............................................5-56
Noise Control System.....................................5-58
Tampering with Noise Control System
Prohibited.................................................5-58
Section 5 Service and Appearance Care
5-1

Filling a Portable Fuel Container
{CAUTION:
Never ®ll a portable fuel container while it is in
your vehicle. Static electricity discharge from
the container can ignite the gasoline vapor.
You can be badly burned and your vehicle
damaged if this occurs. To help avoid injury to
you and others:
·Dispense gasoline only into approved
containers.
·Do not ®ll a container while it is inside a
vehicle, in a vehicle's trunk, pickup bed or
on any surface other than the ground.
·Bring the ®ll nozzle in contact with the
inside of the ®ll opening before operating
the nozzle. Contact should be maintained
until the ®lling is complete.
·Do not smoke while pumping gasoline.
Checking Things Under
the Hood
{CAUTION:
Things that burn can get on hot engine parts
and start a ®re. These include liquids like fuel,
oil, coolant, brake ¯uid, windshield washer and
other ¯uids, and plastic or rubber. You or
others could be burned. Be careful not to drop
or spill things that will burn onto a hot engine.
5-8

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-21.
B. Coolant Surge Tank. See
Engine Coolant on
page 5-30.
C. Air Filter Restriction Indicator (If Equipped). See
Engine Air Cleaner/Filter on page 5-21.
D. Engine Oil Dipstick. See
Engine Oil on page 5-16.
E. Automatic Transmission Dipstick (If equipped).
See
Automatic Transmission Fluid (Except Allison
Transmissionž) on page 5-23orAutomatic
Transmission Fluid (Allison Transmissionž)on
page 5-26.
F. Fan. See
Cooling System on page 5-36.
G. Engine Oil Fill. See
Engine Oil on page 5-16.H. Power Steering Fluid Reservoir. See
Power Steering
Fluid on page 5-42.
I. Remote Negative (-) Terminal (GND). See
Jump
Starting on page 5-48.
J. Remote Positive (+) Terminal. See
Jump Starting on
page 5-48.
K. Brake Fluid Reservoir. See
Brakes on page 5-44.
L. Clutch Fluid Reservoir (If Equipped). See
Hydraulic
Clutch on page 5-29.
M. Underhood Fuse Block. See
Fuses and Circuit
Breakers on page 5-110.
N. Battery. See
Battery on page 5-47.
O. Windshield Washer Fluid Reservoir. See
Windshield
Washer Fluid on page 5-43.
5-11

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-21.
B. Coolant Surge Tank. See
Engine Coolant on
page 5-30.
C. Air Filter Restriction Indicator (If Equipped). See
Engine Air Cleaner/Filter on page 5-21.
D. Engine Oil Dipstick. See
Engine Oil on page 5-16.
E. Automatic Transmission Dipstick (If Equipped).
See
Automatic Transmission Fluid (Except Allison
Transmissionž) on page 5-23orAutomatic
Transmission Fluid (Allison Transmissionž)on
page 5-26.
F. Engine Oil Fill. See
Engine Oil on page 5-16.
G. Fan. See
Cooling System on page 5-36.H. Remote Negative (-) Terminal (GND). See
Jump
Starting on page 5-48.
I. Power Steering Fluid Reservoir. See
Power Steering
Fluid on page 5-42.
J. Remote Positive (+) Terminal. See
Jump Starting on
page 5-48.
K. Brake Fluid Reservoir. See
Brakes on page 5-44.
L. Clutch Fluid Reservoir (If Equipped). See
Hydraulic
Clutch on page 5-29.
M. Underhood Fuse Block. See
Fuses and Circuit
Breakers on page 5-110.
N. Battery. See
Battery on page 5-47.
O. Windshield Washer Fluid Reservoir. See
Windshield
Washer Fluid on page 5-43.
5-13

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-21.
B. Coolant Surge Tank. See
Engine Coolant on
page 5-30.
C. Air Filter Restriction Indicator (If Equipped). See
Engine Air Cleaner/Filter on page 5-21.
D. Engine Oil Dipstick. See
Engine Oil on page 5-16.
E. Automatic Transmission Dipstick (If Equipped).
See
Automatic Transmission Fluid (Except Allison
Transmissionž) on page 5-23orAutomatic
Transmission Fluid (Allison Transmissionž)on
page 5-26.
F. Engine Oil Fill. See
Engine Oil on page 5-16.
G. Fan. See
Cooling System on page 5-36.H. Remote Negative (-) Terminal (GND). See
Jump
Starting on page 5-48.
I. Remote Positive (+) Terminal. See
Jump Starting on
page 5-48.
J. Power Steering Fluid Reservoir. See
Power Steering
Fluid on page 5-42.
K. Brake Fluid Reservoir. See
Brakes on page 5-44.
L. Clutch Fluid Reservoir (If Equipped). See
Hydraulic
Clutch on page 5-29.
M. Underhood Fuse Block. See
Fuses and Circuit
Breakers on page 5-110.
N. Battery. See
Battery on page 5-47.
O. Windshield Washer Fluid Reservoir. See
Windshield
Washer Fluid on page 5-43.
5-15

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.
See
Engine Compartment
Overview on page 5-10
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
Part B: Owner Checks and Services on page 6-12andPart D: Recommended Fluids and Lubricants on
page 6-19.
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-COOLžengine 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
žextended 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, see
Engine Overheating on
page 5-33.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
žcoolant 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.
5-30

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 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
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.
5-31