1996 GMC SIERRA Owners Manual

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 fluid 1evel.u~ to tbe 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 mm 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 Chc d 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.
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
towing, and:
0 Operation above 45 mph (70 km/h) for extended
periods
of time
Vehicles used
in any of these conditions require the
rear axle lubricant be changed every 30,000 miles
(SO 000 km). Fluid capacity is 4.12 quarts (3.9 L).
What to Use
Refer to the Maintenance Schedule to determine what
kind
of lubricant to use. See “Recommended Fluids and
Lubricants”
in the Index.
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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.
Transfer Case
M7hen to Check Lubricant
How to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. See “Periodic Maintenance
Inspections’’
in the Index.
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.
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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.
How to Check Lubricant
If the level is below the bottom of the filler plug hole.
you'll
need to add some lubricant.
If the differential is at operating temperature (warm),
add enough lubricant
to raise the level to the bottom of
the filler plug hole.
If the differential is cold, add enough lubricant to raise
the level
to 1/2 inch (1 2 mm) below 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 system in your vehicle is filled with new
DEX-COOL
TM (orange-colored, silicate-free) engine
coolant. This coolant is designed
to remain in your
vehicle for
5 years or 100,000 miles (1 66 000 km),
whichever occurs first.
The following explains
your cooling system and how
to add coolant when it is low. If you have a problem
with engine overheating, see "Engine Overheating"
in
the Index.
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A 50/50 mixture of water and the proper coolant for
your vehicle
will:
Give freezing prorecrlon down to -34°F (-37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning gages work as they should.
NOTICE:
When adding coolant it is important that you use
DEX-COOL TM (orange-colored, silicate-free)
coolant meeting
GM Specification 6277M.
If silicated coolant 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. use
a mixture
of one-half dum wwter (preferably
distilled) and one-half
DEX-COOL” (orange-colored.
silicate-free) antifreeze that meets
GM Specification
6277M. which
won‘t damage aluminum parts. Use
GM Engine Coolant Supplement (sealer) (GM Part
No. 363462 1 ) with any complete coolant change. If you
use this mixture.
you don’t need to add anything else.
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 mix will. Your vehicle’s coolant warning
system
is set for the proper coolant mix. With
plain water or the wrong mix, 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
50150 mix of clean
water and
DEX-COOL TM (orange-colored,
silicate-free) antifreeze.
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NOTICE:
If you use an improper coolant mix, your engine
could overheat and be badly damaged. The
repair cost wouldn't be covered by your
warranty.
Too much water in the mix can freeze
and crack the engine, radiator, heater core and
other parts.
If you have to add coolant more than four times 8 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 "Clwcking
Coolant"
in the Diesel Engine Supplement.
d
The coolant recovery tank is located on the passenger
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 sho~~ld be up to the HOT mark, or a
little higher.
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Adding Coolant
If you need more coolant, add the proper mix ut tho
cYN-hnt Ix~c'olY!l'\: tmk.
A CAUTION:
\---- -
Turning the radiator pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. With the coolant recovery tank, you will
almost never have to add coolant at the radiator. Never turn the radiator pressure cap
-- even a
little
-- when the engine and radiator are hot.
Add coolant mix at the recovery tank, but be careful not
to spill it.
/rl CAUTION:
r -4
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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Radiator Pressure Cap
(Gasoline Engine)
The radiator pressure cap must be tightly installed with
the arrows on the cap lined LIP 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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