1998 GMC SIERRA coolant temperature

Engine Coolant Heater (If Equipped)
In very cold weather, 0°F (- 1 SOC) or colder, the engine
coolant heater can help. You’ll get easier starting and
better fuel economy during engine warm-up. Usually,
the coolant heater should be plugged in a minimum of
four hours prior to starting your vehicle.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
The engine coolant heater electrical cord
is located
on the driver’s side
of the engine compartment, near
the power steering reservoir.
3. Plug it into a normal, grounded 110-volt AC outlet.
Plugging the cord into an ungrounded outlet
could cause an electrical shock.
Also, the wrong
kind
of extension cord could overheat and cause
a fire. You could be seriously injured. Plug the
cord into a properly grounded three-prong 110-volt
AC outlet. If the cord won’t reach, use a
heavy-duty three-prong extension cord rated for
at least
15 amps.
4. Before starting the engine, be sure to unplug and store
the cord
as it was before to keep it away from moving
engine parts.
If you don‘t, it could be damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind of
oil you have, and some other things. Instead of
trying to list everything here, we ask that you contact
your dealer
in the area where you‘ll be parking your
vehicle. The dealer can give
you the best advice for that
particular area.
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If the light stays on, or comes on when you’re driving,
your vehicle needs service.
If the regular brake system
warning light isn’t on, you still have brakes, but you
don’t have anti-lock brakes.
If the regular brake system
warning light is also on, you don’t have anti-lock brakes
and there‘s a problem
with your regular brakes. See
“Brake System Warning Light” earlier
in this section.
The anti-lock brake system warning light should come
on briefly when you turn the ignition key to RUN. If the
light doesn‘t come on then. have it fixed
so it will be
ready to warn you
if there is a problem.
Engine Coolant Temperature Gage
1
This gage shows the engine
coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read
210°F (100°C) or less. If you are pulling a
load or going up hills, it is normal for the temperature to
fluctuate and approach the
260°F (1 25 “C) mark. If the
gage reaches the
260°F (125°C) mark, it indicates that
the cooling system is working beyond its capacity.
The “Problems on
the Road,” section of this manual shows
what
to do. See “Engine Overheating” in the Index.
Malfunction Indicator Lamp (Service
Engine
Soon Light) (Gasoline Engine)
SERVICE
ENGINE
SOON
Your vehicle is equipped
with a computer which
monitors operation
of the
fuel, ignition and emission
control systems.
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Daytime Running Lamps Indicator Light
:::o e..
This light goes on whenever
the
DRL are on.
Check Gages Light
CHECK
GAGES
This light will come on
briefly when you are
starting the engine.
When
it begins to get dark, the DRL indicator light is a
reminder to turn on your headlamps. If the light comes on and stays on while you are driving,
it could indicate a problem with your vehicle. It could be
a problem with your oil pressure, coolant temperature,
or
some other problem. Check your various gages to see
if they are in the warning zones. If they are, have your
vehicle serviced right away.
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Heating
The heater works best if you keep your windows closed
while using it. On cold days, use the
HEATER or
VENTMEAT setting with the temperature knob in the
red area.
If you use the engine coolant heater before starting your
engine in cold weather,
20” F (-8 O C) or lower, your
heating system will produce warmer air faster, to heat
the passenger compartment
in cold weather.
The use of an engine coolant heater also reduces the
time it takes for the engine to reach normal operating
temperature, and shortens the time it takes the heater to
reach full output. For more information, see “Engine
Coolant Heater” in the Index.
Ventilation System
For mild outside temperatures when little heating or
cooling is needed,
use VENT to direct outside air
through your vehicle. Air will flow through the
instrument panel outlets.
Your vehicle’s ventilation system supplies outside
air to
the inside of your vehicle when
it is moving. With the side
windows closed,
air will flow into the front air inlet grilles,
through the vehicle, and out the
air exhaust valves. Outside air
will also enter the vehicle when the heater or
the air conditioning fan is running, unless you have the
recirculation button pushed in. For more information on
the recirculation button, see “Air Conditioning’’ earlier
in this section.
Your vehicle has air outlets in the center and
on the sides
of your instrument panel. You can move the outlets from
side-to-side or up and down to direct the flow of air, or
close the outlets altogether. When you close an outlet,
it
will increase the flow of air coming out of any outlets
that are open. These outlets do not completely shut off
airflow when in the closed position.
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Driving On Grades
Reduce speed and shift to a lower gear before you 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.
On a long uphill grade, shift down and reduce your
speed
to around 45 mph (70 kdh) to reduce the
possibility
of engine and transmission overheating.
If you have an automatic transmission, you can tow in
AUTOMATIC OVERDRIVE
(@). You may want to
shift the transmission
to THIRD (3) or, if necessary, a
lower gear selection
if the transmission shifts too often
(e.g., under heavy loads and/or hilly conditions).
If
you have a 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).
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’’ in
the Index.
Parking on Hills
You really should not park your vehicle, with a trailer
attached, on a
hill. If something goes wrong, your rig
could start to move. People can be injured, and both
your vehicle and the trailer can be damaged.
But
if you ever have to park your rig on a hill, here’s
how to do it:
1.
2.
3.
4.
Apply your regular brakes, but don’t shift into
PARK
(P) yet for an automatic transmission, or into
gear for a manual transmission.
Have someone place chocks under the trailer wheels.
When the wheel chocks are
in place, release the
regular brakes until the chocks absorb the load.
Reapply the regular brakes. Then apply your parking brake and
shift into PARK (P) for an automatic
transmission, or REVERSE (R)
for a manual
transmission.
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5. Put the transfer case in NEUTRAL (N). See
“Four-Wheel Drive’’
in the Index for the proper
procedure to select NEUTRAL
(N).
6. When the vehicle is hooked up. release the
parking brake.
7. Turn the ignition key to OFF.
Four- Wheel-Drive Vehicles (Electronic
Transfer Case)
Eml Limits -- 35 mph (55 km/JZ), 50 milc?s (80 kndh)
If your vehicle is four-wheel drive with an electronic
transfer case, use the following directions:
I. Engage the parking brake.
2. Turn the ignition key to ON.
3. Clamp the steering wheel in a straight-ahead position
with
a clamping device designed for towing service.
(Do not use the vehicle’s steering column lock for this.)
4. Put the transmission in NEUTRAL (N).
5. Put the transfer case in 2 High (2HI).
6. When the vehicle is hooked up, release the
parking brake.
7. Turn the ignition key to OFF.
NOTICE:
If your vehicle is equipped with four-wheel drive
and the towing limits must be exceeded, a towing
dolly must be used under the front wheels or
vehicle/powertrain damage will occur.
I NOTICE:
Towing pickup models from the rear while loaded
with heavy cargo may cause the frame side rails
to flex sufficiently to allow the pickup box to
contact the cab and could cause damage to the
cab and/or box.
Engine Overheating (Gasoline Engine)
You will find a coolant temperature gage on your
vehicle’s instrument panel. See “Engine Coolant
Temperature Gage”
in the Index.
If your vehicle has a diesel engine, see “Engine
Overheating”
in the Diesel Engine Supplement.
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How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you may need to add some lubricant.
When the differential is cold, add enough lubricant to
raise the level to 1/2 inch (12
mrn) below the filler
plug hole.
When the differential is at operating temperature
(warm), add enough lubricant to raise the level to the
bottom
of the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See “Recommended Fluids and
Lubricants” in the Index.
Engine Coolant
The cooling s stem 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 I
(240 000 km) whichever occurs first, if you add only ~
DEX-COOL’ extended life coolant.
8
The following explains your cooling system and how
to add coolant when it is low. If you have a problem
i
with engine overheating, see “Engine Overheating” in 1
the Index.
A 50/50 mixture of water and DEX-COOL@ coolant will: 1
0 Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 OF (1 29 O C).
Protect against rust and corrosion.
0 Help keep the proper engine temperature.
0 Let the warning gages work as they should.
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Radiator Pressure Cap
(Gasoline Engine)
The radiator pressure cap must be tightly installed with
the arrows
on the cap lined up with the overflow tube on
the radiator filler neck.
~~~ ~
NOTICE:
Your radiator cap is a 15 psi (105 kPa)
pressure-type cap and 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 overflow tube on the radiator
filler neck.
Thermostat
Engine coolant temperature is controlled by a thermostat
in the engine coolant system. The thermostat stops the
flow of coolant through the radiator until the coolant
reaches a preset temperature.
When you replace your thermostat, an
AC@ thermostat
is recommended.
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