1998 GMC SIERRA Owners Manual

3. Check both sides of the dipstick, and read the lower
level. The fluid level must be in the COLD area for a
cold check or in the
HOT area or cross-hatched area
for a
hot check.
4. If the fluid level is in the acceptable range, push the
dipstick back in all the way; then flip the handle
down
to lock the dipstick in place.
io dd Fluid
Refer to the Maintenance Schedule to determine what
kind
of transmission fluid to use. See “Recommended
Fluids and Lubricants”
in the Index. Add
fluid only after checking the transmission fluid
while
it is hot. (A cold check is used only as a
reference.)
If the fluid level is low, add only enough of
the proper fluid
to bring the level up to the HOT area for
a hot check. It doesn’t take much fluid, generally less
than one pint
(0.5 L). Don’t overfill.
I NOTICE:
We recommend you use only fluid labeled
DEXRON@-111, because fluid with that label is
made especially for your automatic transmission.
Damage caused by fluid other than DEXRON-111
is not covered by your new vehicle warranty.
After adding fluid, recheck the fluid level as
described under “How to Check.”
When the correct fluid level is obtained, push the
dipstick back
in all the way; then flip the handle
down to lock the dipstick
in place.
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Manual Transmission Fluid
When to Check
A good time to have it checked is when the engine oil is
changed. However, the fluid in your manual
transmission doesn’t require changing.
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 fdse reading.
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.
Check the fluid level only when your engine is off, the
vehicle is parked on a level place and the transmission is
cool enough
for you to rest your fingers on the
transmission case.
Then, follow these steps:
I. Remove the filler plug.
2. Check that the lubricant level is up to the bottom of
the filler plug hole.
3. If the fluid level is good, install the plug and be sure
it is fully seated. If the fluid level is low, add more
fluid as described in the next steps.
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How to Add Fluid
Here’s how to add fluid. Refer to the Maintenance
Schedule to determine what kind of fluid to use. See
”Recommended Fluids and Lubricants”
in the Index.
1. Remove the filler plug.
2. Add fluid at the filler plug hole. Add only enough
fluid to bring the tluid level up to the bottom of the
filler plug hole.
3. Install the filler plug.
Be sure the plug is fully seated.
Hydraulic Clutch
The hydraulic clutch system in your vehicle is
self-adjusting. A slight amount of play (1/4 inch to
1/2 inch or 6 lnm to 12 mm) in the pedal is normal.
It isn‘t a good idea to “top off’ your clutch fluid. Adding
fluid won’t correct a leak.
A fluid loss in this system could
indicate a problem. Have
the system inspected and repaired.
When to Check and What to Use
Refer to the Maintenance
Schedule, Owner Checks
and Services,
to determine
how often you should check
the fluid level
in your clutch
master cylinder reservoir
and for the proper fluid. See
“Owner Checks and
Services” and
“Recommended Fluids and
Lubricants” in the Index.
How to Check
The proper fluid 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.
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Rear Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often to check
the lubricant and when to change it. See
“Scheduled Maintenance Services” in the Index.
How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you’ll need to add some lubricant.
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.
C3 (3500 HD) Trucks Equipped with Dana
Rear
Axle
Additional rear axle scheduled maintenance is required
on
3500 HD models equipped with Dana rear axles
when they are driven under the following conditions:
Extreme loading (at or near GVWR) or trailer
Operation above 45 mph (70 km/h) for extended
Vehicles used in any of these conditions require the
rear axle lubricant be changed every
30,000 miles
(50 000 km). Fluid capacity is 4.12 quarts (3.9 L).
towing, and:
periods of time.
Four-wheel Drive
Most lubricant checks in this section also apply to
four-wheel-drive vehicles. However, they have two
additional systems that need lubrication.
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Transfer Case
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check
the lubricant. See “Periodic Maintenance
Inspections” in the Index.
How to Check I>--’- --’ :::It
If the level is below the bottom of the filler plug hole,
you’ll need to add some lubricant. 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.
Front Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant and when to change
it. See
“Scheduled Maintenance Services”
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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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.
What to Use
Use a mixture of one-half clean water (preferably
distilled) and one-half
DEX-COOL@ coolant which
won’t damage aluminum
parts. If you use this 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 water and
DEX-COOL@ coolant.
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- ~ ~~
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.
Checking Coolant
If your vehicle has a diesel engine, see “Checking
Coolant”
in the Diesel Engine Supplement.
,:. . .,. ..... I.. .;> .:... ...,,.. ::l:. ..
.. .
The coolant recovery tank is located on the passenger’s
side at the rear corner
of the engine compartment.
When your engine
is cold, the coolant level should be at
the
COLD mark, or a little higher. When your engine is
warm,
the level should be up to the HOT mark, or a
little higher.
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