2003 CHEVROLET SILVERADO coolant temperature

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

Coolant Surge Tank Pressure Cap
SeeEngine Compartment
Overview on page 5-10for
more information on
location.
The coolant surge tank pressure cap must be fully
installed on the coolant surge tank.
Notice:Your pressure cap is a pressure-type cap
and must be tightly installed to prevent coolant loss
and possible engine damage from overheating.
See ªCapacities and Speci®cationsº for more
information.
Engine Overheating
You will ®nd a coolant temperature gage on your
vehicle's instrument panel. SeeEngine Coolant
Temperature Gage on page 3-47. In addition, you will
®nd a LOW COOLANT LEVEL, ENGINE OVERHEATED
and a REDUCED ENGINE POWER message in the
Driver Information Center on the instrument panel. See
Driver Information Center (DIC) on page 3-54.
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. See ªEngine Oilº in the Index.
5-33

100,000 Miles (166 000 km)
qInspect spark plug wires.An Emission Control
Service.
qReplace spark plugs.An Emission Control Service.
qChange automatic transmission ¯uid and ®lter if
the vehicle's GVWR is over 8600 lbs, if the
vehicle has an Allison transmission or if the vehicle is
mainly driven under one or more of these conditions:
þ In heavy city traffic where the outside
temperature regularly reaches 90ÉF (32ÉC) or
higher.
þ In hilly or mountainous terrain.
þ When doing frequent trailer towing.
þ Uses such as found in taxi, police or delivery
service.
qIf you haven't used your vehicle under severe service
conditions listed previously and, therefore, haven't
changed your automatic transmission ¯uid, change
both the ¯uid and ®lterqAutomatic Transfer Case Only: Change transfer case
¯uid
qExcept 8.1L V8 Engine: Inspect Positive Crankcase
Ventilation (PCV) valve.
An Emission Control
Service.
150,000 Miles (240 000 km)
qDrain, ¯ush and re®ll cooling system (or every
60 months since last service, whichever occurs ®rst).
See
Engine Coolant on page 5-30for what to use.
Inspect hoses. Clean radiator, condenser, pressure
cap and neck. Pressure test the cooling system
and pressure cap.
An Emission Control Service.
qChange ®ve-speed manual transmission ¯uid (with
4300 V6 or 4800 V8 engines only).
qInspect engine accessory drive belt.
An Emission
Control Service.
200,000 Miles (332 000 km)
q6000 V8 Engine Only: Change ®ve-speed manual
transmission ¯uid.
6-11

Child Restraints (cont.)
Top Strap...................................................1-42
Where to Put the Restraint...........................1-41
Chime Level Adjustment.................................3-125
Cigarette Lighter.............................................3-20
Cleaning Aluminum or Chrome-Plated Wheels . . . 5-105
Cleaning Exterior Lamps/Lenses......................5-104
Cleaning Fabric/Carpet...................................5-100
Cleaning Glass Surfaces................................5-102
Cleaning Interior Plastic Components...............5-102
Cleaning Leather...........................................5-102
Cleaning the Mirror.........................................2-56
Cleaning the Top of the Instrument Panel.........5-102
Cleaning the Windshield and Wiper Blades.......5-104
Cleaning Tires..............................................5-105
Cleaning Vinyl..............................................5-101
Cleaning......................................................5-100
Inside of Your Vehicle.................................5-100
Outside of Your Vehicle..............................5-103
Underbody Maintenance.............................5-106
Video Screen............................................3-125
Weatherstrips............................................5-103
Climate Control System...................................3-20
Dual Automatic............................................3-25
Dual..........................................................3-22
Clutch, Hydraulic.............................................5-29
Compact Disc Messages................3-84, 3-97, 3-110
Compass Calibration...............................2-56, 2-57
Compass Operation.........................................2-57Compass Variance..................................2-55, 2-58
Content Theft-Deferrent....................................2-18
Control of a Vehicle.......................................... 4-5
Coolant.........................................................3-47
Engine Temperature Gage............................3-47
Heater, Engine............................................2-24
Surge Tank Pressure Cap.............................5-33
Cooling System..............................................5-36
Crew Cab......................................................1-53
Cruise Control Light........................................3-52
Cruise Control................................................3-11
Cupholder(s)..................................................2-64
Current and Past Model Order Forms................7-10
Customer Assistance Information........................ 7-7
Courtesy Transportation.................................. 7-7
Customer Assistance for Text Telephone (TTY)
Users....................................................... 7-4
Customer Assistance Offices........................... 7-4
Customer Satisfaction Procedure..................... 7-2
GM Mobility Program for Persons with
Disabilities................................................ 7-5
Reporting Safety Defects to General Motors...... 7-9
Reporting Safety Defects to the Canadian
Government.............................................. 7-9
Reporting Safety Defects to the United States
Government.............................................. 7-8
Roadside Assistance Program......................... 7-5
Service Publications Ordering Information......... 7-9
4

Electrical System (cont.)
Power Windows and Other Power Options....5-109
Windshield Wiper Fuses.............................5-109
Electrochromic Mirror Operation................2-54, 2-57
Electronic Transfer Case..................................2-41
Emissions Inspection and Maintenance
Programs...................................................3-51
ENGINE COOLANT HOT.................................3-66
Engine Coolant Level Check.............................6-12
Engine Hour Meter Display...............................3-35
Engine Oil Additives........................................5-19
Engine Oil and Chassis Lubrication Scheduled
Maintenance................................................. 6-5
Engine Oil Level Check...................................6-12
ENGINE OVERHEATED..................................3-66
Engine..........................................................5-21
Air Cleaner/Filter.........................................5-21
Battery.......................................................5-47
Check and Service Engine Soon Light............3-49
Compartment Overview................................5-10
Coolant Heater............................................2-24
Coolant Temperature Gage...........................3-47
Coolant......................................................5-30
Cooling System Inspection............................6-17
Exhaust.....................................................2-51
Fan Noise..................................................5-41
Oil .............................................................5-16
Overheating................................................5-33Engine (cont.)
Starting......................................................2-22
Entertainment System....................................3-125
Cleaning the Video Screen..........................3-125
DVD Distortion..........................................3-122
Entry Lighting.................................................3-18
Environmental Concerns..................................4-25
Exit Lighting...................................................3-18
Express Down Windows..................................2-16
Extended Cab and Crew Cab...........................1-50
Extended Cab................................................1-53
Extender, Safety Belt.......................................1-31
Exterior Lamps...............................................3-14
F
Filter.............................................................5-21
Engine Air Cleaner......................................5-21
Finding a PTY Station
(RDS and XMŸ).......................3-78, 3-88, 3-101
Finding a Station....................3-73, 3-76, 3-86, 3-99
Finish Care..................................................5-104
Finish Damage.............................................5-106
Five-Speed (VORTECŸ 4300 V6 and
4800 V8 Engines)........................................2-30
Five-Speed (VORTECŸ 6000 V8 Engine)...........2-29
Fixed Mast Antenna.......................................3-125
6

Flash-To-Pass Feature....................................... 3-9
Flat Tire, Changing.........................................5-80
Flat Tire........................................................5-79
Fluid.............................................................5-23
Automatic Transmission........................5-23, 5-26
Manual Transmission....................................5-28
Power Steering...........................................5-42
Windshield Washer......................................5-43
FM Stereo....................................................3-123
Fog Lamps....................................................3-16
Folding the Rear Seat....................................... 1-8
Following Distance..........................................4-86
Footnotes........................................................ 6-5
Four-Wheel Drive....................................2-33, 5-56
Four-Wheel-Drive Light....................................3-52
Front Axle Locking Feature...............................2-33
Front Axle......................................................5-57
Front Reading Lamps (If Equipped)...................3-18
Front Storage Area.........................................2-65
Fuel Information Button....................................3-57
FUEL LEVEL LOW.........................................3-66
Fuel............................................................... 5-4
Additives...................................................... 5-5
California Fuel.............................................. 5-5
Filling a Portable Fuel Container..................... 5-8
Filling Your Tank........................................... 5-6
Fuels in Foreign Countries.............................. 5-6Fuel (cont.)
Gage.........................................................3-53
Gasoline Octane........................................... 5-4
Gasoline Speci®cations.................................. 5-5
Low Warning Light.......................................3-54
System Inspection.......................................6-17
Fuses..........................................................5-110
Fuses and Circuit Breakers.........................5-110
Windshield Wiper.......................................5-109
G
Gage............................................................3-47
Engine Coolant Temperature.........................3-47
Fuel..........................................................3-53
Oil Pressure...............................................3-51
Speedometer..............................................3-35
Tachometer.................................................3-35
Transmission Temperature.............................3-47
Voltmeter Gage...........................................3-42
Gasoline......................................................... 5-4
Octane........................................................ 5-4
Speci®cations............................................... 5-5
Getting Familiar with Off-Road Driving................4-26
Glove Box.....................................................2-64
GM Mobility Program for Persons with
Disabilities.................................................... 7-5
7

Tires (cont.)
Changing a Flat Tire....................................5-80
Dual Tire Operation.....................................5-70
If a Tire Goes Flat.......................................5-79
In¯ation -- Tire Pressure...............................5-69
Inspection and Rotation................................5-71
Uniform Tire Quality Grading.........................5-75
Wheel Alignment and Tire Balance.................5-76
Wheel Replacement.....................................5-76
When It Is Time for New Tires......................5-73
To Use the Engine Coolant Heater....................2-24
Top Strap Anchor Location...............................1-44
Top Strap......................................................1-42
Torque Lock (Automatic Transmission)...............2-48
Total Weight on Your Vehicle's Tires..................4-84
Tow/Haul Mode Light.......................................3-53
Tow/Haul Mode, Overdrive Disable....................3-53
Tow/Haul Mode
(Automatic Transmission)..............................2-28
Towing..........................................................4-95
Power Take-Off (PTO)..................................4-95
Recreational Vehicle.....................................4-55
Towing a Trailer..........................................4-68
Your Vehicle...............................................4-55
TRACTION ACTIVE........................................3-70
Traction.........................................................4-10
Assist System (TAS)....................................4-10
Manual Selectable Ride................................4-12
Off Light.....................................................3-46Traction (cont.)
Trailer Brakes.................................................4-85
Trailer Wiring Harness.....................................4-89
Trailer...........................................................4-67
Recommendations.......................................4-67
TRANS HOT IDLE ENGINE (Allison
Transmission
žOnly).....................................3-71
Transfer Case and Front Axle (Four-Wheel Drive)
Inspection...................................................6-18
Transfer Case........................................5-54, 5-56
TRANSMISSION HOT.....................................3-70
Transmission Operation, Automatic....................2-25
Transmission Operation, Manual........................2-29
Transmission, Transaxle, Transfer Case Unit
Repair Manual............................................7-10
Transmission..................................................5-23
Fluid, Automatic..................................5-23, 5-26
Fluid, Manual..............................................5-28
Temperature Gage.......................................3-47
Up-Shift Light..............................................3-43
Transportation Options...................................... 7-7
Traveling to Remote Areas...............................4-26
Trip Information Button....................................3-55
Trip Odometer................................................3-35
Truck-Camper Loading Information....................4-65
Turn and Lane Change Signals.......................... 3-8
TURN SIGNAL ON.........................................3-71
Turn Signal/Multifunction Lever........................... 3-7
Turn Signals When Towing a Trailer..................4-87
17