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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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Power Steering Fluid
When to Check Power Steering Fluid
It is not necessary to regularly check power steering
fluid unless
you suspect there is a leak in the system or
you hear an unusual noise. A fluid loss in this system
could indicate
a problem. Have the system inspected
and repaired.
How To Check Power Steering Fluid
When the engine cotnparttnent is cool, unscrew the cap
and
wipe the dipstick with a clean rag. Replace the cap
and completely tighten
it. Then remove the cap again
and
look at the fluid level on the dipstick.
The level should he at the FULL COLD mark. If
necessary, add only enough fluid to bring the level up
to the mark.
What to Use
Refer to the Maintenance Schedule to determine what
kind
of fluid to use. See “Recommended Fluids and
Lubricants” in the Index. Always use the proper fluid.
Failure to
use the proper fluid can cause leaks and
damage hoses and seals.
Windshield Washer Fluid
What to Use
When you need windshield washer fluid, be sure to read
the manufacturer’s instructions before use. If you will be
operating
your vehicle in an area where the tetnperature
may
fill1 below freezing, use a fluid that has sufficient
protection against freezing.
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Brakes
Brake Fluid
Your brake master cylinder
reservoir
is here. It is filled
I 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.
A CAUTION0
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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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 inspected every 6,000 to 8,000 miles
(10 000 to 13 000 km) for any signs of unusual wear. If
unusual wear
is present, 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.
I
FRT FRT
I
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.
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 [Ires with different load ranges
or tread designs (such as all season vs. on/off road) than
the rear tires, don’t rotate your tires front to rear.
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Section 7 Maintenance Schedule
I IMPORTANT: I
KEEP ENGINE OIL
AT THE PROPER
LEVEL AND CHANGE AS
RECOMMENDED
This section covers the maintenance required for your
vehicle. Your vehicle needs these services to retain its
safety, depe.ndability and emission control performance.
7- 1
Protection
Plan
Introduction
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle
in good working condition. but also helps the
environment.
All 1-ecommended maintenance procedures
are important. Improper vehicle maintenance can even affect the quality of the air we breathe. Improper fluid
levels or the wrong
tire inflation can increase the level
of emissions fr6m your vehicle. To help protect our
environlnent, and to keep your vehicle in good
condition, please maintain your vehicle properly.
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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 ma~ntenance 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 whenever you stop for fuel.
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 perf‘ormed, 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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