2006 GMC SIERRA engine

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 remote positive (+) terminal cover,
if equipped, 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
To get an accurate reading, the vehicle should be on a
level surface.
The proper level for the 1500 Series is from
5/8 inch to 1 5/8 inch (15 mm to 40 mm) below
the bottom of the ller plug hole.
The proper level for the 1500HD Series,
2500 Series and 2500HD Series with the
6.0L V8 engine (RPO LQ4) is from 0 to 1/2 inch
(0 to 13 mm) below the bottom of the ller plug hole.1500 Series Shown, 2500 Series Similar
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The proper level for the 2500HD with the 6.6L diesel
engine (RPO LLY) or 8.1L V8 engine (RPO L18), and
3500 Series is from 0.6 to 0.8 inch (17 mm to 21 mm)
below the bottom of the ller plug hole.
Add only enough uid to reach the proper level.
What to Use
To determine what kind of lubricant to use see
Recommended Fluids and Lubricants (Gasoline Engine)
on page 6-14.
Four-Wheel Drive
Lubricant checks in this section also apply to these
vehicles. There are two additional systems that need
lubrication.
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
Manual Transfer Case
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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’ll 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.
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 (Gasoline Engine) on page 6-14.
Front Axle
When to Check 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. Automatic Transfer Case
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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 ller plug hole,
located on the front axle, you may need to add some
lubricant:
When the differential is cold, add enough lubricant to
raise the level to 0 to 3/8 inch (9.5 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
To determine what kind of lubricant to use see
Recommended Fluids and Lubricants (Gasoline Engine)
on page 6-14.
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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; or
2. 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 specications.
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.
Modication 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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Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected for wear
and cracking. SeeScheduled Maintenance (Gasoline
Engine) on page 6-4for more information.
Replacement blades come in different types and are
removed in different ways. For proper type and length,
seeNormal Maintenance Replacement Parts (Gasoline
Engines) on page 6-18.
To replace the windshield wiper blade assembly do the
following:
1. Lift the wiper arm away from the windshield.2. Push the release lever (B) to disengage the hook
and push the wiper arm (A) out of the blade (C).
3. Push the new wiper blade securely on the wiper arm
until you hear the release lever click into place.
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Tire Size
The following examples show the different parts of a
tire size.
(A) Passenger (P-Metric) Tire:The United States
version of a metric tire sizing system. The letter P as the
rst character in the tire size means a passenger vehicle
tire engineered to standards set by the U.S. Tire and Rim
Association.(A) Light Truck (LT-Metric) Tire:The United States
version of a metric tire sizing system. The letters LT as
the rst two characters in the tire size means a light
truck tire engineered to standards set by the U.S. Tire
and Rim Association.
(B) Tire Width:The three-digit number indicates the
tire section width in millimeters from sidewall to sidewall.
(C) Aspect Ratio:A two-digit number that indicates
the tire height-to-width measurements. For example,
if the tire size aspect ratio is 75, as shown in item C of
the light truck (LT-Metric) tire illustration, it would
mean that the tire’s sidewall is 75% as high as it is wide.
(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire.
The letter R means radial ply construction; the letter D
means diagonal or bias ply construction; and the letter B
means belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel in inches.
(F) Service Description:The service description
indicates the load range and speed rating of a tire.
The load index can range from 1 to 279. Speed ratings
range from A to Z. Passenger (P-Metric) Tire
Light Truck (LT-Metric) Tire
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