
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
towing, and:
periods of time.
Vehicles used in any
of these conditions require the rear
axle lubricant be changed every
30,000 miles (50 OOO km).
Fluid capacity is 4.12 quarts (3.9 L).
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 Front Axle
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.
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 cooling system in your vehicle is filled with
new DEX-COOL@ engine coolant. This coolant is
designed to remain in your vehicle for
5 years or
150,000 miles (240
000 km), whichever occurs first,
if
you add only DEX-COOL@ extended life 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.
A 50/50 mixture of water and the proper coolant for
your vehicle will:
0 Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 “F (1 29°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
0 Let the warning gages work as they should.
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.
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Brakes
Brake Fluid
Your brake master cylinder
reservoir is here. It
is filled
with
DOT-3 brake fluid.
There are
only two reasons why the brake fluid level in
the reservoir might go down. The first is that the brake
fluid goes down to an acceptable level during normal
brake lining wear. When new linings are put in, the fluid
level goes back up. The other reason
is that fluid is
leaking out of the brake system.
If it is, you should have
your brake system fixed, since a leak means that sooner
or later your brakes won’t work well, or won’t work
at all.
So, it isn’t a good idea to “top off’ your brake fluid.
Adding brake fluid won’t correct a leak.
If you add fluid
when your linings are worn, then
you’ll have too much
fluid when you get new brake linings. You should add
(or remove) brake fluid,
as necessary, only when work is
done on the brake hydraulic system.
I
If you have too much brake fluid, it can spill
on the engine. The fluid will burn if the engine
is hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake
fluid only when work is done on the brake
hydraulic system.
Refer to the Maintenance Schedule to determine when to
check your brake fluid. See “Periodic Maintenance
Inspections”
in the Index.
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When to Check
Check your tires once a month or more. Also, check the
tire pressure of the spare tire.
How to Check
Use a good quality pocket-type gage to check tire
pressure.
You can’t tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they’re underinflated.
Be sure
to put the valve caps back on the valve stems.
They help prevent leaks by keeping out
dirt and moisture.
Tire Inspection and Rotation
Tires should be rotated every 6,000 to 8,000 miles
(10 000 to 13 000 km). Any time you notice unusual
wear, rotate your tires as soon as possible and check
wheel alignment.
Also check for damaged tires or
wheels. See “When It’s Time for New Tires” and
“Wheel Replacement” later
in this section for more
information. If your vehicle has dual rear wheels, also
see “Dual Tire Operation” later in this section. The
purpose of regular rotation is to achieve more
uniform wear for all tires
on the vehicle. The first
rotation is the most important. See “Scheduled
Maintenance Services” in the Index for scheduled
rotation intervals.
I FRT FRT
I
If your vehicle has single rear wheels, always use one of
the correct rotation patterns shown here when rotating
your tires.
If your vehicle has front tires with different load ranges
or tread designs (such as all season vs. odoff road)
than
the rear tires, don’t rotate your tires front to rear.
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Section 7 Maintenance Schedule
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This section covers the maintenance required for your vehicle. Your vehicle needs these services to retain its safety,
dependability and emission control performance.
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7-3 1
Introduction
Part
A: Scheduled Maintenance Services
Short Trip/City Maintenance Schedule
Long Trip/City Maintenance Schedule
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7-54
?art B: Owner Checks and Services
?art C: Periodic Maintenance Inspections
?art
D: Recommended Fluids and Lubricants
'art E: Maintenance Record
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How This Section is Organized
The remainder of this section is divided into five parts:
“Part
A: Scheduled Maintenance Services” shows
what to have done and how often. Some of these
services can be complex,
so unless you are technically
qualified and have the necessary equipment, you should
let your dealer’s service department or another qualified
service center do these jobs.
Performing maintenance work on a vehicle can
be dangerous. In trying to do some jobs, you can
be seriously injured.
Do your own maintenance
work only if you have the required know-how
and the proper
tools and equipment for the job.
If you have any doubt, have a qualified
technician do the work.
If you are skilled enough to do some work on your
vehicle, you will probably want to get the service
information GM publishes. See “Service and Owner
Publications”
in the Index. “Part
B: Owner Checks and
Services” tells you what
should be checked and when. It also explains what you
can easily do to help keep your vehicle in good condition.
“Part
C: Periodic Maintenance Inspections” explains
important inspections that your GM dealer’s service
department or another qualified service center
should perform.
“Part
D: Recommended Fluids and Lubricants” lists
some products GM recommends to help keep your
vehicle properly maintained. These products, or their
equivalents, should be used whether you do the work
yourself or have it done.
“Part
E: Maintenance Record” provides a place for
you to record the maintenance performed on your
vehicle. Whenever any maintenance
is performed, be
sure
to write it down in this part. This will help you
determine when your next maintenance should be done.
In addition, it is a good idea to keep your maintenance
receipts. They may be needed to qualify your vehicle for
warranty repairs.
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Part A: Scheduled Maintenance
Services
Using Your Maintenance Schedule
We at General Motors want to help you keep your vehicle
in good working condition. But we don’t know exactly
how you’ll drive it.
You may drive very short distances
only
a few times a week. Or you may drive long distances
all the time in
very hot, dusty weather. You may use your
vehicle
in making deliveries. Or you may drive it to work,
to do errands or
in many other ways.
Because of all the different ways people use their GM
vehicles, maintenance needs vary. You may even need
more frequent checks and replacements than you’ll find
in
the schedules in this section. So please read this
section and note how you drive. If you have any
questions
on how to keep your vehicle in good
condition, see your GM dealer.
This part tells you the maintenance services you should
have done and when you should schedule them. If you
go to your dealer for your service needs, you’ll know
that GM-trained and supported service people will
perform the work using genuine
GM parts.
The proper fluids
and lubricants to use are listed in Part D.
Make sure whoever services your vehicle uses these. All parts should
be replaced and all necessary repairs done
before you
or anyone else drives the vehicle.
These schedules are for vehicles that:
0
0
0
0
carry passengers and cargo within recommended
limits. You will find these limits on your vehicle’s
Certificatioflire label. See “Loading Your Vehicle”
in the Index.
are driven
on reasonable road surfaces within legal
driving limits.
are driven off-road in the recommended manner. See
“Off-Road Driving With Your Four-Wheel-Drive
Vehicle’’
in the Index.
use the recommended fuel. See “Fuel”
in the Index.
Selecting the Right Schedule
First you’ll need to decide which of the two schedules is
right for your vehicle. Here’s how to decide which
schedule to follow:
Gasoline engine vehicles and diesel engine vehicles
have different maintenance requirements. If you have a
diesel engine, follow
a schedule designated for diesel
engine vehicles only.
See the Diesel Engine Supplement for diesel engine
maintenance schedules.
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