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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.
SeeScheduled Maintenance on page 6-5.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.
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. SeePart C: Recommended
Fluids and Lubricants on page 6-29.
Rear Axle Shift Motor
When to Check and Change Fluid
If you have an optional air-shift two-speed, controlled
traction, or locking differential type rear axle, a good time
to check the fluid level in the axle shift motor is when
the rear axle lubricant is checked. Use refrigerant
oil (shift motor only).
How to Check Fluid
Remove the plug on the front plate of the axle shift
motor, add enough fluid to raise the level to the bottom
of the filler plug hole, then replace the plug.
What to Use
Refer to your Maintenance Schedule to determine what
kind of lubricant to use. SeePart C: Recommended
Fluids and Lubricants on page 6-29.
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Noise Control System
Tampering with Noise Control
System Prohibited
The following information relates to compliance with
federal noise emission standards for vehicles with
a Gross Vehicle Weight Rating (GVWR) of more than
10,000 lbs (4 536 kg). The Maintenance Schedule
provides information on maintaining the noise control
system to minimize degradation of the noise emission
control system during the life of your vehicle. The noise
control system warranty is given in your warranty
booklet.
These standards apply only to vehicles sold in the
United States.
Federal law prohibits the following acts or the causing
thereof:
1. The removal or rendering inoperative by any
person, other than for purposes of maintenance,
repair or replacement, of any device or element of
design incorporated into any new vehicle for
the purpose of noise control, prior to its sale or
delivery to the ultimate purchaser or while it is in
use; or2. The use of the vehicle after such device or element
of design has been removed or rendered inoperative
by any person.
Among those acts presumed to constitute tampering are
the acts listed below.Insulation:
•
Removal of the noise shields or any underhood
insulation.
Engine:
•
Removal or rendering engine speed governor (if
equipped) inoperative so as to allow engine
speed to exceed manufacturer specifications.
Fan and Drive:
•
Removal of fan clutch (if equipped) or rendering
clutch inoperative.
•Removal of the fan shroud (if equipped).
Air Intake:
•
Removal of the air cleaner silencer.
•Modification of the air cleaner.
Exhaust:
•
Removal of the muffler and/or resonator.
•Removal of the exhaust pipes and exhaust pipe
clamps.
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2. Push the release lever and slide the wiper assembly
toward the driver’s side of the vehicle.
3. Install a new blade by reversing Steps 1 and 2.
Other Service Items
Fuel Filter
Fuel Filter (Gasoline Engines)
The steel fuel filter is located near the engine
compartment on the driver’s side of the vehicle. See
your Maintenance Schedule for recommended service
intervals.
If your vehicle is equipped with the optional Davco
spin-on type filter, it is located on the driver’s side
frame rail.
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Fuel Filter (Diesel Engines)
If you have a diesel engine, your fuel filter is located in
the engine compartment on the driver’s side of the
vehicle, or along the driver’s side frame rail. SeeFuel
Filter Replacementearlier in this section for further
information.
Also seeScheduled Maintenance on page 6-5for
recommended service intervals.
Primary Fuel Filter and Water
Separator
If you have a diesel
engine, you may have this
spin-on filter. It is located
on the driver’s side
frame rail.It has a clear plastic drain bowl at the bottom. Check
the drain bowl occasionally for any water or particles.
To drain the bowl, do the following:
1. Shut off the engine.
2. Partially open the drain valve at the bottom of the
filter.
SeeEngine Oil (Caterpillar
®Diesel Engine) on
page 5-20orEngine Oil (Gasoline Engine) on page 5-20
orEngine Oil (DURAMAX™ Diesel) on page 5-25for
proper disposal procedures.
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6. Install a new gasket whenever you take out the
cylinder. Use only one gasket and spread a light
film of clean oil on it before installation.
7. Put in the new cylinder. Turn it clockwise until it just
starts to contact the gasket.
8. Tighten the cylinder another half turn (180 degrees).
Don’t over-tighten.
9. Retighten the cylinder clamp.
Front Wheel Bearings with
Oil-Filled Hubs
If your vehicle has oil-filled
hubs, occasionally check
to see if they have enough
oil. You can tell if there
is oil there by using
the circular gage on the
sight glass.If there isn’t, clean the rubber fill plug in the center of
the glass, and then remove it. Be careful not to
allow any dirt or water to get into the oil. Add enough of
the recommended oil to bring it up to the level mark
that you’ll see on the glass.
Refer to your Maintenance Schedule for the proper oil
to use.
When you fill the hub, check the glass again after
driving a short distance. It takes a while for the oil to
flow through the system, and you may find that you have
to add a little more to fill it to the proper level. Be sure
not to overfill the hub.Air Conditioning System
Every now and then, have your dealership check your
air conditioning system to be sure it has not lost
any cooling ability. If you think the system is not working
properly, have your GM dealer check it out as soon
as possible.
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{CAUTION:
If wheel studs are damaged, they can break. If
all the studs on a wheel broke, the wheel could
come off and cause a crash. If any stud is
damaged because of a loose-running wheel, it
could be that all of the studs are damaged. To
be sure, replace all studs on the wheel. If the
stud holes in a wheel have become larger, the
wheel could collapse in operation. Replace any
wheel if its stud holes have become larger or
distorted in any way. Inspect hubs and hub
piloted wheels for damage. Because of loose
running wheels, piloting pad damage may
occur and require replacement of the entire
hub, for proper centering of the wheels. When
replacing studs, hubs, wheel nuts or wheels,
be sure to use GM original equipment parts.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel could
come off and cause a crash. When you change
a wheel, remove any rust or dirt from places
where the wheel attaches to the vehicle. In an
emergency, you can use a cloth or a paper
towel to do this; but be sure to use a scraper
or wire brush later, if you need to, to get all the
rust or dirt off.
How Often to Check
Wheel tightness is so important you should have a
technician check nut tightness on all wheels with
a torque wrench after your first 100 miles (160 km), and
then 1,000 miles (1 600 km) after that. Be sure to
repeat this service whenever you have a tire removed
or serviced. SeeScheduled Maintenance on page 6-5
for further information.
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Maintenance Schedule......................................6-2
Introduction...................................................6-2
Maintenance Requirements..............................6-2
Your Vehicle and the Environment....................6-2
How This Section is Organized.........................6-3
Part A: Scheduled Maintenance Services...........6-4
Using Your Maintenance Schedule....................6-4
Scheduled Maintenance Supplements................6-4Scheduled Maintenance...................................6-5
Part B: Owner Checks and Services................6-24
At Each Fuel Fill..........................................6-24
At Least Twice a Year...................................6-25
At Least Once a Year...................................6-28
Part C: Recommended Fluids and Lubricants. . . .6-29
Part D: Maintenance Record..........................6-31
Section 6 Maintenance Schedule
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Maintenance Schedule
Introduction
Important: Keep engine oil at the proper level and
change as recommended.
Have you purchased the GM Protection Plan? The Plan
supplements your new vehicle warranties. See your
Warranty and Owner Assistance booklet or your dealer
for details.
Maintenance Requirements
Maintenance intervals, checks, inspections and
recommended fluids and lubricants as prescribed in this
manual are necessary to keep your vehicle in good
working condition. Any damage caused by failure
to follow scheduled maintenance may not be covered by
warranty.
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle in good working condition, but also helps the
environment. 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 from your vehicle. To help protect
our environment, and to keep your vehicle in good
condition, be sure to maintain your vehicle properly.
6-2