1999 GMC C-SERIES engine coolant

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5-30
CAUTION:
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like 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 wouldn't
get the overheat warning. Your engine could
catch fire and you or others could be burned.
Use a 50/50 mixture of clean, drinkable water
and coolant.
NOTICE:
In cold weather, water can freeze and crack the
engine, radiator, heater core and other parts. So
use the recommended coolant.
CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot
enough. Don't spill coolant on a hot engine.
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5-32
3. Then fill the coolant surge tank with the proper
coolant mixture, up to the COLD FULL mark.
4. With the coolant surge
tank pressure cap off,
start the engine and let it
run until you can feel the
upper radiator hose
getting hot. Watch out
for the engine fan.
By this time, the coolant level inside the coolant surge
tank may be lower. If the level is lower, add more of the
proper mixture to the coolant surge tank until the level
reaches the COLD FULL mark.
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6-
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6-1
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 Service
6
-4 Fuel (Gasoline Engine)
6
-5 Diesel Fuel Requirements and Fuel System
6
-6 Fuels in Foreign Countries (Gasoline Engines)
6
-7 Filling Your Tank
6
-8 Filling a Portable Fuel Container
6
-9 Checking Things Under the Hood
6
-11 Noise Control System
6
-13 Engine Oil (Gasoline Engine)
6
-17 Engine Oil (Caterpillar
Diesel Engine)
6
-17 Engine Air Cleaner/Filter
6
-18 Automatic Transmission Fluid
6
-19 Manual Transmission Fluid
6
-20 Rear Axle
6
-20 Rear Axle Shift Motor (Option)
6
-21 Radiator Pressure Cap (Gasoline Engines)
6
-22 Surge Tank Pressure Cap (Diesel Engines)
6
-22 Thermostat6
-23 Engine Coolant (Gasoline Engine)
6
-27 Engine Coolant (Caterpillar
Diesel Engine)
6
-28 Power Steering Fluid
6
-29 Windshield Washer Fluid
6
-30 Brakes
6
-36 Electric/Hydraulic Parking Brake Fluid
6
-42 Battery
6
-44 Other Service Items
6
-48 Tires
6
-59 Appearance Care
6
-59 Cleaning the Inside of Your Vehicle
6
-63 Cleaning the Outside Your Vehicle
6
-66 GM Vehicle Care/Appearance Materials
6
-67 Vehicle Identification Number (VIN)
6
-67 Service Parts Identification Label
6
-68 Electrical System
6
-74 Capacities and Specifications
6
-77 Air Conditioning Refrigerants
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6-11
Then place the prop rod,
located on the panel, where
the arrow is pointing.
CAUTION:
Things that burn can get on hot engine parts and
start a fire. These include liquids like gasoline or
diesel fuel, oil, coolant, brake fluid, windshield
washer and other fluids, 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.
Before closing the hood or access panels, be sure all the
filler caps are on properly.
Noise Control System
The following information relates to compliance with
Federal noise emission standards for vehicles with a
Gross Vehicle Weight Rating (GVWR) of more than
10,000 lbs. (4 536 kg). The Maintenance Schedule
provides information on maintaining the noise control
system to minimize degradation of the noise emission
control system during the life of your vehicle. The
noise control system warranty is given in your
Warranty booklet.
These standards apply only to vehicles sold in the
United States.
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6-21
Radiator Pressure Cap
(Gasoline Engines)
The radiator pressure cap
must be tightly installed
with the arrows on the cap
lined up with the top of the
overflow tube. This will
prevent coolant loss and
possible engine damage
from overheating.
When you replace your radiator pressure cap, an
ACDelco

cap is recommended.
NOTICE:
Your radiator pressure cap is a 9 psi (62kPa)
pressure
-type cap for use with medium duty
cooling systems only. It must be tightly installed
to prevent coolant loss and possible engine
damage from overheating. Be sure the arrows on
the cap line up with the top of the overflow tube.
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6-22
Surge Tank Pressure Cap
(Diesel Engines)
The surge tank pressure cap
must be tightly installed
with the arrows on the cap
lined up with the top tube of
the coolant surge tank.
When you replace your surge tank pressure cap, an
ACDelco

cap is recommended.
NOTICE:
Your surge tank pressure cap is a 9 psi (62kPa)
pressure
-type cap for use with medium duty
cooling systems only. It must be tightly installed
to prevent coolant loss and possible engine
damage from overheating. Be sure the arrows on
the cap line up with the top tube of the coolant
surge tank.
Thermostat
Engine coolant temperature is controlled by one or more
thermostats in the engine cooling system. The
thermostat stops the flow of coolant through the radiator
until the coolant reaches a preset temperature.
When you replace your thermostat, an ACDelco


thermostat is recommended for gasoline engines.
Caterpillar
parts are recommended for diesel engines.
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6-23
Engine Coolant (Gasoline Engine)
The cooling system in your vehicle is filled 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 first, 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, see ªEngine Overheatingº in
the Index.
A 50/50 mixture of clean, drinkable water and
DEX
-COOL
coolant will:

Give freezing protection down to
-34F (-37C).

Give boiling protection up to 252F (122C).

Protect against rust and corrosion.

Help keep the proper engine temperature.

Let the warning lights and gages work as
they should.
NOTICE:
When adding coolant, it is important that you
use only DEX
-COOL (silicate-free) coolant.
If coolant other than DEX-COOL is 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 first. Damage caused by the
use of coolant other than DEX
-COOL is not
covered by your new vehicle warranty.
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6-24 What to Use
Use a mixture of one-half clean, drinkable water and
one
-half DEX-COOL
coolant 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 like 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 wouldn't
get the overheat warning. Your engine could
catch fire and you or others could be burned.
Use a 50/50 mixture of clean, drinkable water
and DEX
-COOL
coolant.
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.
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