1998 GMC SIERRA oil 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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Oil Pressure Gage
0
Y3
80
The oil pressure gage shows
the engine oil pressure in psi (pounds per square inch)
when the engine
is running.
Canadian vehicles indicate
pressure
in kPa (kilopascals).
Oil pressure may vary with engine speed, outside
temperature
and oil viscosity, but readings above the
low pressure zone indicate the
normal operating range.
A reading in the low pressure zone may be caused by a
dangerously low oil level or some other problem causing
low oil pressure. Check
your oil as soon as possible.
I
Don’t keep driving if the oil pressure is low. If
you do, your engine can become
so hot that it
catches fire.
You or others could be burned.
Check your oil as soon as possible and have your
vehicle serviced.
I NOTICE:
Damage to your engine from neglected oil problems
can be costly and is not covered by your warranty.
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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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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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What Kind of Engine Oil to Use
Oils recommended for your vehicle can be identified by
looking for the “Starburst” symbol. This symbol
indicates that
the oil has been certified by the American
Petroleum Institute (API).
Do not use any oil which
does not carry this Starburst symbol.
If
you change your own oil,
be sure you use oil that has
the Starburst symbol on the
front of the oil container.
If you have your oil changed for you, be sure the oil put
into your engine
is American Petroleutn Institute
certified for gasoline engines.
You should
also use the proper viscosity oil for your
vehicle, as shown in the following chart:
RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
SAL VISCOSITY GRADE OIL
FOR THE EXPECTED TEMPERATURE RANGE.
LOOK
FOR THIS
SYMBOL
COLD
WEATHER
DO NOT USE SAE 2OW-50 OR ANY OTHER GRADE OIL NOT RECOMMENDED
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As shown in the chart, SAE 5W-30 is best for your
vehicle. However,
you can use SAE 1OW-30 if it’s going
to be
0°F (- 18 “C) or above. These numbers on an oil
container show
its viscosity, or thickness. Do not use
other viscosity oils, such
as SAE 20W-50.
NOTICE:
Use only engine oil with the American Petroleum
Institute Certified For Gasoline Engines “Starburst” symbol. Failure to use the
recommended oil can result in engine damage not
covered by your warranty.
GM Goodwrench@ oil meets all the requirements for
your vehicle.
If you are in an area where the temperature falls below
-20°F (-29°C)’ consider using either an SAE 5W-30
synthetic oil or an
SAE OW-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Don’t add anything to your oil. Your dealer is ready to
advise if
you think something should be added.
When to Change Engine Oil
If any one of these is true for you, use the short tripkity
maintenance schedule:
Most trips are less than 5 to 10 miles (8 to 16 km).
This is particularly important when outside
temperatures are below freezing.
Most trips include extensive idling (such as frequent
driving
in stop-and-go traffic).
You operate your vehicle in dusty areas or
off-road frequently.
You frequently tow a trailer.
The vehicle is used for delivery service, police, taxi
or other commercial application.
Driving under these conditions causes engine
oil to
break down sooner.
If any one of these is true for your
vehicle,
then you need to change your oil and filter
every
3,000 miles (5 000 km) or 3 months -- whichever
occurs first.
If none of them is true, use the long trip/highway
maintenance schedule. Change the oil and filter every
7,500 miles (12 500 km) or 12 months -- whichever
occurs first. Driving a vehicle with
a fully warmed
engine under highway conditions causes engine
oil to
break down slower.
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Automatic Transmission Fluid
If your vehicle has a diesel engine, see “Automatic
Transmission Fluid”
in the Diesel Supplement.
When to Check and Change
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change both the fluid and filter every
50,000 miles
(83
000 km) if the vehicle’s GVWR is over 8,600 or
if the vehicle is mainly driven under one or more of
these conditions:
In heavy city traffic where the outside temperature
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery service.
regularly
reaches
90°F (32°C) or higher.
If your vehicle’s GVWR is not over 8,600 and you do not
use your vehicle under any
of these conditions, change the
fluid and filter every
100,000 miles (166 000 km).
See “Scheduled Maintenance Services’’ in the Index.
How to Check
Because this operation can be a little difficult, you
may choose to have this done at your
GM dealership
Service Department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
NOTICE:
Too much or too little fluid can damage your
transmission.
Too much can mean that some of
the fluid could come
out and fall on hot engine
parts or exhaust system parts, starting a fire.
Be
sure to get an accurate reading if you check your
transmission fluid.
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving:
When outside temperatures are above 90°F (32°C).
At high speed for quite a while.
In heavy traffic -- especially in hot weather.
While pulling a trailer.
To get the right reading, the fluid should be at normal
operating temperature, which is
180°F to 200°F (82°C
to 93°C). See “Checking Transmission Fluid Hot“ in
the Index.
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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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