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Then, follow these steps:
1. 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.
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 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 linkage in your vehicle is self-adjusting. A slight
amount
of play (1/4 inch to 1/2 inch) in the pedal is normal.
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When to Check and What to Use
Refer to the
Maintenance Schedule
to determine how
often
you should
check the
fluid level
in your clutch master
cylinder reservoir and
d 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.
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.
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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 H.D.) Trucks Equipped with Dana Rear Axle
Additional rear axle scheduled maintenance is required on 3500 H.D.
models equipped with Dana rear axles when they are driven under the
following conditions:
0 Extreme loading (at or near GVWR) or trailer towing, and:
Operation above 45 mph for extended periods of time
Vehicles used
in any of these conditions require the rear axle lubricant (SAE
8OW-90 - GL-5) be changed every 3 months or 3,000 miles, whichever
comes first.
To reduce required maintenance, SAE 75W-140 synthetic gear lubricant
may be used. With the use of synthetic
SAE 75W-140 lubricant, the fluid
change intervals may be increased to 30,000 miles. Before using SAE
75W-140, it is important to drain and flush the axle with clean mineral
based (non-synthetic) axle lubricant. Fluid capacity is 4.12 qts. (3.9L).
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
When to Check Lubricant
Refer to the Maintenance Schedule to determine how often to check the
lubricant. See “Periodic Maintenance Inspections”
in the Index.
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How to Check Lubricant
What to Use
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.
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.
How to Check Lubricant
If the level is below the bottom of the filler plug hole, you’ll need to add
some lubricant.
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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
( 12 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 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.
The proper coolant for your vehicle will:
Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 262°F (128°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning gages work as they should.
What to Use
Use a mixture of one-half cleun water (preferably distilled) and one-half
antifreeze that meets “GM Specification 6038-M,” which won’t damage
aluminum parts.
You can also use a recycled coolant conforming to “GM
Specification 6038-M.” Use GM Coolant Supplement (Sealer) with a
complete coolant flush and refill. If you use this mixture. you don’t need to
add anything else.
A 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 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 50/50 mix of clean
water and
a proper 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.
Some conditions. such as air trapped
in the cooling system. can affect the
coolant level
in thc radiator. Check the coolant level when the engine is cold
and
follow the steps under “Adding Coolant“ for the proper way to add
coolant.
If you have to add coolant more than lour timcs a ycar, 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.
Adding Coolant - Gasoline Engine
The coolant reco\wy
tank is located on the
passenger side
at the
rear comer
of the
engine compartment.
To Check Coolant
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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To Add Coolant
If you need more coolant, add the proper mix at the coolant recovery tank.
A CAUTION:
arning 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.
A 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.
Adding Coolani - Diesel Engine
The coolant surge tank
is located on the
passenger side at the
rear corner of the
engine compartment.
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To Check Coolant
A CAUTION:
Turning the surge tank pressure cap when the engine and
radiator are hot can allow steam and scalding liquids to blow out
and burn you badly. Never turn the surge tank pressure cap
-
even a little - when the engine and radiator are hot.
When your engine is cold, the coolant level should be at the COLD mark, or
a little higher.
If this light comes on, it means you’re low on engine coolant.
To Add Coolant
If you need more coolant, add the proper mix ut the surge tmk, but only
when the engine is cool. If the surge tank is empty, see “Engine
Overheating”
in the Index for the proper fill procedure.
A 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.
When replacing the pressure cap, make sure it is tight.
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