1998 GMC SIERRA radiator cap

If you get the overheat warning with no sign of steam,
try this for
a minute or so:
1. If you have an air conditioner, turn it off.
2. Turn on your heater to full hot at the highest fan
speed and open the window
as necessary.
3. If you’re in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving
-- AUTOMATIC OVERDRIVE (@)
for automatic transmissions.
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about
10 minutes.
If the warning doesn’t come back on, you can
drive normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there’s still no sign
of steam, push the accelerator until
the engine speed
is about twice as fdst as normal idle
speed. Bring the engine speed back to normal idle speed
after two or three minutes. Now see if the warning stops.
But then, if you still have the warning, turn ofthe
engine
and get everyone out of the vehicle until it
cools down.
You may decide not to lift the hood but to get service
help right away.
Cooling System -- Gasoline Engines
When you decide it’s safe to lift the hood, here’s what
you’ll see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Fan(s)
5-15
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A CAUTION:
Steam and scalding liquids from a
system can blow out and burn you badly. They
are under pressure, and if you turn the radiator
pressure cap
-- even a little -- they can come out
at high speed. Never turn the cap when the
cooling system, including the radiator pressure
cap,
is hot. Wait for the cooling system and
radiator pressure cap to cool if you ever have to
turn the pressure cap.
I
5-19
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How to Add Coolant to the Radiator
1. You can remove the radiator pressure cap when the
cooling system, including the radiator pressure cap and
upper radiator hose,
is no longer hot. Turn the pressure
cap slowly counterclockwise until it first stops. (Don't
press down while
turning the pressure cap.)
2. Then keep turning the pressure cap, but now push
down
as you turn it. Remove the pressure cap.
If you hear
a hiss, wait for that to stop. A hiss means
there is still some pressure left.
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3. Fill the radiator with the proper DEX-COOL@
coolant mixture, up to the base of the filler neck.
(See “Engine Coolant” in the Index for more
information about the proper mixture.)
4. Then fill the coolant recovery tank to the COLD mark.
5. Put the cap back on the coolant recovery tank, but
leave the radiator pressure cap off.
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6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out
for the
engine cooling
fan(s).
7. By this time, the coolant level inside the r' d d' mor
filler neck may be lower. If the level is lower, add
more of the proper DEX-COOL@ coolant mixture
through the filler neck
until the level reaches the
base
of the filler neck.
8. Then replace the pressure cap. At any time during
this procedure
if coolant begins to flow out of the
filler neck, reinstall the pressure cap. Be sure the
arrows on the pressure
cap line up like this.
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Section 6 Service and Appearance Care
Here you will find information about the care of your vehicle. This section begins with service and fuel information,
and then it shows how to check important fluid and lubricant levels. There is also technical information about your
vehicle, and
a part devoted to its appearance care.
6-2
6-3
6-5
6-6
6- 8
6-9
6- 13
6- 14
6-18
6-2
I
6-24
6- 25
6-26
6-26
6-28 6-32
6-32 Service
Fuel (Gasoline Engine)
Fuels
in Foreign Countries (Gasoline Engines)
Filling Your Tank (Gasoline Engine)
Filling a Portable Fuel Container
Checking Things Under the Hood
Noise Control System
Engine Oil (Gasoline Engine)
Air Cleaner Filter (Gasoline Engine)
Automatic Transmission Fluid
Manual Transmission Fluid
Hydraulic Clutch
Rear Axle
Four-wheel Drive
Engine Coolant Radiator Pressure Cap (Gasoline Engine)
Thermostat
, 6-33
6-3 3
6-35
6-39
6-39
6-50
6-5
1
6-6 1
6-62
6-65 6-69
6-70
6-70
' 6-76
6-77 6-79 Power
Steering Fluid
Windshield Washer Fluid
Brakes
Battery
Bulb Replacement
Windshield Wiper Blade Replacement
Tires
Appearance Care
Cleaning the Inside
of Your Vehicle
Cleaning the Outside of Your Vehicle
Appearance Care Materials Chart
Vehicle Identification Number (VIN)
Electrical System Replacement
Bulbs
Capacities and Specifications
Air Conditioning Refrigerants
6-1
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“VORTEC” 4300,5000,5700 Engine, “VORTEC” 5700 engine shown, locations for other engines similar.
When you lift
up the hood you’ll see:
A. Battery
G. Automatic Transmission L. Clutch Fluid Reservoir
B. Air Cleaner
Dipstick
(If Equipped) (If Equipped)
C. Radiator Cap H. Fan M. Windshield Washer Fluid
D. Coolant Recovery Tank I. Power Steering Fluid Reservoir Reservoir
E. Air Filter Restriction Indicator J. Engine Oil Fill N. FuseRelay Center
F. Engine Oil Dipstick K. Brake Fluid Reservoir
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“VORTEC” 7400 Engine
A. Battery
B. Coolant Recovery Tank
C. Air Cleaner
D. Radiator Cap
E. Air Filter Restriction Indicator
F. Engine Oil Dipstick
G. Automatic Transmission L. Clutch Fluid Reservoir
Dipstick (If Equipped)
(If Equipped)
H. Engine Oil Fill M. Windshield Washer
I. Fan Fluid Reservoir
J. Power Steering Fluid Reservoir N. Fusemelay Center
K. Brake Fluid Reservoir
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