2008 CHEVROLET SILVERADO Owners Manual

Notice:If the jumper cables are connected or
removed in the wrong order, electrical shorting may
occur and damage the vehicle. The repairs would
not be covered by your warranty. Always connect
and remove the jumper cables in the correct
order, making sure that the cables do not touch
each other or other metal.
A. Heavy, Unpainted Metal Engine Part or Remote
Negative (−) Terminal
B. Good Battery or Remote Positive (+) and Remote
Negative (−) Terminals
C. Dead Battery or Remote Positive (+) TerminalTo disconnect the jumper cables from both vehicles
do the following:
1. Disconnect the black negative (−) cable from the
vehicle that had the bad battery.
2. Disconnect the black negative (−) cable from the
vehicle with the good battery.
3. Disconnect the red positive (+) cable from the
vehicle with the good battery.
4. Disconnect the red positive (+) cable from the
other vehicle.
5. Return the positive (+) terminal cover, to its original
position.
Jumper Cable Removal
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Rear Axle
When to Check Lubricant
It is not necessary to regularly check rear axle uid
unless you suspect there is a leak or you hear an
unusual noise. A uid loss could indicate a problem.
Have it inspected and repaired.
All axle assemblies are lled by volume of uid during
production. They are not lled to reach a certain
level. When checking the uid level on any axle,
variations in the readings can be caused by factory ll
differences between the minimum and the maximum
uid volume. Also, if a vehicle has just been driven
before checking the uid level, it may appear lower than
normal because uid has traveled out along the axle
tubes and has not drained back to the sump area.
Therefore, a reading taken ve minutes after the vehicle
has been driven will appear to have a lower uid
level than a vehicle that has been stationary for an hour
or two. Remember that the rear axle assembly must
be supported to get a true reading.
How to Check Lubricant
2500HD with 6.0L
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To get an accurate reading, the vehicle should be on a
level surface.
For all 4.3L, 4.8L and 5.3L 1500 Series applications,
the proper level is 0.04 inches to 0.75 inches
(1.0 mm to 19.0 mm) below the bottom of the ller
hole, located on the rear axle. Add only enough
uid to reach the proper level.
For all 6.0L 1500 Series applications, the proper
level is from 0.6 inches to 1.6 inches (15 mm to
40 mm) below the bottom of the ller plug
hole, located on the rear axle. Add only enough
uid to reach the proper level.
For all 6.0L 2500HD Series applications, the proper
level is from 0 to 0.5 inches (0 mm to 13 mm)
below the bottom of the ller plug hole, located on
the rear axle. Add only enough uid to reach
the proper level.
For all 6.6L DURAMAX DIESEL 2500HD Series
applications and all 3500 Series applications,
the proper level is from 0.6 inches to 0.8 inches
(17 mm to 21 mm) below the bottom of the ller plug
hole, located on the rear axle. Add only enough
uid to reach the proper level.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeeRecommended Fluids
and Lubricants on page 6-14. All Other Series and Engines
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Four-Wheel Drive
Lubricant checks in this section also apply to these
vehicles.
Transfer Case
When to Check Lubricant
It is not necessary to regularly check transfer case uid
unless you suspect there is a leak, or you hear an
unusual noise. A uid loss could indicate a problem.
Have it inspected and repaired.
How to Check Lubricant
A. Fill Plug
B. Drain PlugElectric Shift Transfer Case
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A. Fill Plug
B. Drain PlugA. Fill Plug
B. Drain Plug
To get an accurate reading, the vehicle should be on a
level surface.
If the level is below the bottom of the ller plug hole,
located on the transfer case, you will need to add some
lubricant. Add enough lubricant to raise the level to
the bottom of the ller plug hole. Use care not to
overtighten the plug. Manual Shift Transfer Case
Active Transfer Case
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When to Change Lubricant
Refer to the Maintenance Schedule to determine how
often to change the lubricant. SeeScheduled
Maintenance (Gasoline Engine) on page 6-4.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeeRecommended Fluids
and Lubricants on page 6-14.
Front Axle
When to Check and Change Lubricant
It is not necessary to regularly check front axle uid
unless you suspect there is a leak or you hear an
unusual noise. A uid loss could indicate a problem.
Have it inspected and repaired.
How to Check Lubricant
A. Fill Plug
B. Drain Plug1500 Series
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To get an accurate reading, the vehicle should be on a
level surface.
When the differential is cold, add enough lubricant
to raise the level from 0 (0 mm) to 1/8 inch
(3.2 mm) below the ller plug hole.
When the differential is at operating temperature
(warm), add enough lubricant to raise the level
to the bottom of the ller plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeeRecommended Fluids
and Lubricants on page 6-14.
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; or
2. The use of the vehicle after such device or
element of design has been removed or rendered
inoperative by any person.
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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 the
vehicle has one, inoperative so as to allow engine
speed to exceed manufacturer specications.
Fan and Drive:

Removal of fan clutch, if the vehicle has one, or
rendering clutch inoperative.
Removal of the fan shroud, if the vehicle has one.
Air Intake:

Removal of the air cleaner silencer.
Modication of the air cleaner.
Exhaust:

Removal of the muffler and/or resonator.
Removal of the exhaust pipes and exhaust pipe
clamps.
Headlamp Aiming
The vehicle has a visual optical headlamp aiming
system. The aim of the headlamps have been preset at
the factory and should need no further adjustment.
However, if the vehicle is damaged in a crash, the aim
of the headlamps can be affected and adjustment
can be necessary.
If oncoming vehicles ash their high beams at you, this
can mean the vertical aim of your headlamps needs
to be adjusted.
It is recommended that the vehicle is taken to your
dealer/retailer for service if the headlamps need to be
adjusted. It is possible however, to re-aim the
headlamps as described.
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