GMC 2006 DURAMAX User manual

Features and Controls ..................................... 2-1
Starting and Operating Your Vehicle ............. 2-2
Instrument Panel ............................................. 3-1
Warning Lights, Gages and Indicators ........... 3-2
Driving Your Vehicle ....................................... 4-1
Towing ..................................................... 4-2
Service and Appearance Care .......................... 5-1
Diesel Fuel Requirements and Fuel System ..... 5-2
Checking Things Under the Hood ............... 5-18
Capacities and Specifications ..................... 5-50
Maintenance Schedule
..................................... 6-1
Maintenance Schedule ................................ 6-2
2006 DURAMAX
®
Diesel Engine M
Index ......................................................................... 1

General Motors, GM, GMC, CHEVROLET, the GM
Emblem, the GMC Truck Emblem, the CHEVROLET
Emblem, and the names SIERRA, SILVERADO,
SAVANA and EXPRESS are registered trademarks
of General Motors Corporation.
This manual contains information that pertains to the
operation of your diesel engine. It also contains your
Diesel Maintenance Schedule. The sections in this
manual correspond to the sections in your owner manual.
This manual, along with your owner manual, will assist
you in the proper use and maintenance of your vehicle.
Keep this manual with the owner manual in your vehicle,
so it will be there if you ever need it while you are on
the road. If you sell your vehicle, leave this manual
and the owner manual with the vehicle.
This manual includes the latest information at the time it
was printed. We reserve the rights to make changes in
the product after that time without notice.
Canadian Owners
A French language copy of this manual can be obtained
from your dealer or from:
Helm, Incorporated
P.O. Box 07130
Detroit, MI 48207
Litho in U.S.A.
Part No. 15105920 B Second Printing
©
2005 General Motors Corporation. All Rights Reserved.
ii

Starting and Operating Your Vehicle .................2-2
Starting the Diesel Engine ...............................2-2
Winter Cover (Pickup Models Only) ...................2-6
Fuel Operated Heater (FOH) (Van Models Only) ....2-8
Engine Coolant Heater ....................................2-8
Section 2 Features and Controls
2-1

Starting and Operating
Your Vehicle
Starting the Diesel Engine
Your diesel engine starts differently than a gasoline
engine.
Automatic Transmission
Move your shift lever to PARK (P) or NEUTRAL (N).
Your engine won’t start in any other position — that’s a
safety feature. To restart when you’re already moving,
use NEUTRAL (N) only.
Notice: Do not try to shift to PARK (P) if your
vehicle is moving. If you do, you could damage
the transmission. Shift to PARK (P) only when your
vehicle is stopped.
Manual Transmission
(Pickup Models Only)
Move your shift lever to neutral and hold the clutch pedal
to the floor while starting the engine. Your vehicle won’t
start if the clutch pedal is not all the way down — that’s
a safety feature.
Starting Your Engine
1. Turn your ignition key to RUN.
Observe the wait to start light. See Wait to Start
Light on page 3-7. This light may not come on if
the engine is hot.
2. As soon as the wait to start light goes off,
immediately turn the ignition key to START.
When the engine starts, let go of the key.
Your engine has a fast warm-up glow plug system.
The wait to start light will illuminate for a much
shorter time than most diesel engines, due to the
rapid heating of the glow plug system.
Notice: Holding your key in START for longer than
15 seconds at a time will cause your battery to be
drained much sooner. And the excessive heat can
damage your starter motor.
Notice: If the wait to start light stays on after
starting your vehicle, your vehicle may not run
properly. Have your vehicle serviced right away.
3. If the engine does not start after 15 seconds of
cranking, turn the ignition key to LOCK. Wait
one minute for the starter to cool, then try the
same steps again.
If you’re trying to start your engine after you’ve run
out of fuel, follow the steps in Running Out of Fuel
on page 5-11.
2-2

When your engine is cold, let it run for a few minutes
before you move your vehicle. This lets oil pressure
build up. Your engine will sound louder when it’s cold.
Notice: If you are not in an idling vehicle and the
engine overheats, you would not be there to see the
overheated engine indication. This could damage
your vehicle. Do not let your engine run when you are
not in your vehicle.
Cold Weather Starting (Diesel Engine)
The following tips will help you get good starting in
cold weather.
Use the recommended engine oil when the outside
temperature drops below freezing. See Engine Oil on
page 5-21. When the outside temperature drops below
0° F (–18°C), use of the engine coolant heater is
recommended.
If you experience longer cranking times, notice an
unusual amount of exhaust smoke or are at higher
altitudes (over 7,000 ft. or 2 135 m), you may use your
engine coolant heater. See Engine Coolant Heater
on page 2-8.
See Diesel Fuel Requirements and Fuel System on
page 5-2 for information on what fuel to use in cold
weather.
If Your Diesel Engine Won’t Start
If you’ve run out of fuel, look at Running Out of Fuel
on page 5-11. See Diesel Fuel Requirements and Fuel
System on page 5-2.
If you’re not out of fuel, and your engine won’t start,
do this:
Turn your ignition key to RUN. Immediately after the wait
to start light goes off, turn the ignition key to START.
If the light doesn’t go off, wait a few seconds, then try
starting your engine again. See your dealer as soon
as you can for a starting system check.
If the light comes on and then goes off and you know your
batteries are charged, but your engine still won’t start,
your vehicle needs service.
If the light does not come on when the engine is cold,
your vehicle needs service.
If your batteries don’t have enough charge to start your
engine, see “Battery” in the owner’s manual Index.
Be sure you have the right oil for your engine, and that
you’ve changed the oil at the proper times. If you use
the wrong oil, your engine may be harder to start.
2-3

Be sure you are using the proper fuel for existing
weather conditions. See Diesel Fuel Requirements
and Fuel System on page 5-2.
If the engine starts, runs a short time, then stops, your
vehicle needs service.
{CAUTION:
Do not use gasoline or starting aids, such as
ether, in the air intake. They could damage
your engine. There could also be a fire, which
could cause serious personal injury.
Elevated Idle/Exhaust Restrictor
The engine has a cold temperature high idle and exhaust
restrictor feature which elevates the engines idle speed
from 680 to 1200 rpms, and restricts the exhaust gas
flow, when outside temperatures are below 32°F (0°C),
and the engine coolant temperature is below 150°F
(65°C.) This feature enhances heater performance
by raising the engine coolant temperature faster.
For pickup models, this feature can be turned off and
on using the DIC steering wheel control buttons. If your
vehicle is not equipped with the DIC steering wheel
control buttons, do the following to turn on this feature:
1. Turn the ignition to RUN, with the vehicle off.
2. Press the accelerator pedal to the floor and hold
while quickly pressing the brake pedal three times
in less than eight seconds.
3. Release the accelerator pedal and start the engine.
When the engine is started, it will slowly ramp up to the
high idle speed after a delay of a few seconds up to
approximately two minutes. For this method to work
properly there must be no throttle or brake pedal faults.
The engine idle speed will return to normal once the
following conditions are met:
•Once engine coolant temperature reaches
150°F (65°C).
•Air intake temperature reaches 32°F (0°C).
2-4

The high idle speed will be temporarily interrupted
and the engine speed will return to normal if any of
the following conditions occur:
•The brake pedal is applied.
•The accelerator pedal is pressed.
•The automatic transmission is shifted out of
PARK (P) or NEUTRAL (N).
•The clutch pedal on the manual transmission is
pressed (pickup models).
•Vehicle speed is detected.
Once these inputs are removed, the engine idle speed
will slowly ramp back up to high idle after the normal
delay, if the conditions for engine coolant temperature
and air intake temperature are still met.
Manual High Idle System
(Van Models Only)
If your vehicle has this
feature, the manual high
idle switch is located
on the instrument panel.
This system can be used to increase your engine idle
speed whenever the following conditions are met:
•The brake pedal is not pressed.
•The vehicle speed is below about 5 mph (8 km/h).
•The transmission is in NEUTRAL (N) or PARK (P).
The manual high idle feature is activated by pressing
the switch on the instrument panel. When the switch is
pressed again, or any of the previous conditions are not
met, manual high idle will be deactivated. The manual
high idle has been preset at the factory. Your dealer may
change the setting to fit your needs.
2-5

Winter Cover (Pickup Models Only)
If your vehicle includes a winter cover, it will enhance
heater performance and will reduce the amount of time it
takes to warm the inside of your vehicle in extremely cold
conditions (below 0°F (−18°C)). The winter cover consists
of two parts, the front bumper cover (if equipped) and
the grille cover. The winter cover installs over the front
bumper of your vehicle and restricts the air flowing to
the engine compartment by covering the radiator grille.
Usage Guidelines
The winter cover should only be used while operating
your vehicle in extremely cold temperatures. In these
temperatures, the vehicle does not need a large amount
of air to properly cool the engine. During periods of
operation when more airflow is required to cool the
vehicle, the winter cover should not be used. The
following usage guidelines will allow adequate airflow
for proper radiator grille and air cooler performance:
•Do not use the winter cover when temperatures are
expected to be above 32°F (0°C). Use of the cover
in these conditions could cause your vehicle to
overheat. If this happens while the cover is being
used, remove the cover.
•Do not use the winter cover if towing a trailer. The
added power needed to tow a trailer requires the
radiator grille to have full airflow under all conditions.
Your vehicle may overheat if the cover is used while
towing a trailer.
•Do not modify the cover. The winter cover does
not cover some sections of the front of the vehicle
because these openings are needed to provide
enough airflow to the radiator grille and air cooler
in extremely cold temperatures.
2-6

•When the winter cover is used, the temperature
sensor found on the inside rearview mirror will not
function properly. The temperature that is shown will
be incorrect.
Installation Instructions
The following instructions explain how to install and
remove your vehicle’s winter cover. When installing
or removing the cover please refer to the “Usage
Guidelines” mentioned previously. When you first try to fit
the cover it may appear to be undersized. This is due to
the nature of the special vinyl, which will stretch during
installation to ensure a tight fit. For this reason, the initial
installation of the cover is best performed when the winter
cover is warm. If you are required to use a front license
plate, simply cut the black stitches on the back of the
patch.
Grille Cover Installation
1. Pre-bend all the small black tabs into the
shape of a J.
2. Fasten the snaps.
3. Wrap the elastic loop around the hood stopper.
4. Hook all the tabs to the edge of the grille.
5. Hook all clips to the bottom of the grille.
Lower Cover Installation
1. Pre-bend all of the small black tabs into the
shape of a J.
2. Fasten each tab to
edge of the bumper,
as illustrated.
To remove the winter cover, reverse the steps listed
previously.
2-7

Fuel Operated Heater (FOH)
(Van Models Only)
If your vehicle includes a fuel operated heater (FOH),
it will enhance heater performance and will reduce the
amount of time it takes to warm the inside of your vehicle
in cold conditions below 40°F (4.4°C). The fuel operated
heater is installed in the frame rail on the driver’s side of
the vehicle and uses diesel to warm up the engine
coolant, which finally warms up the passenger’s cabin
air. The FOH works automatically, depending on the
fuel level, engine coolant temperature and outside air
temperature. It works only with the engine running.
Engine Coolant Heater
In very cold weather, 0°F (−18°C) or colder, the engine
coolant heater can help. You’ll get easier starting
and better fuel economy during engine warm-up.
Usually, the coolant heater should be plugged in a
minimum of four hours prior to starting your vehicle.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
The cord is located in the engine compartment,
on the passenger’s side of the vehicle, near the
right side engine mount.
3. Plug it into a normal, grounded 110-volt AC outlet.
{CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a fire. You could be seriously injured.
Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord
will not reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
2-8

4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts. If you don’t, it could
be damaged.
How long should you keep the coolant heater plugged in?
The answer depends on the outside temperature. You
may wish to use your coolant heater to improve ease
of starting at temperatures between 0°F (−18°C)
and −20°F (−29°C).
Keep the coolant heater plugged in for
a minimum of four hours. At temperatures below −20°F
(−29°C), the coolant heater should remain plugged in for
at least eight hours. It will not harm either the coolant
heater or the vehicle to leave the coolant heater plugged
in longer than the times stated. Be sure to remove and
store the cord before starting the engine. See Diesel
Fuel Requirements and Fuel System on page 5-2 for
information on what fuel to use in cold weather.
2-9

✍NOTES
2-10

Warning Lights, Gages and Indicators ...............3-2
Instrument Panel Cluster .................................3-2
Malfunction Indicator Lamp ..............................3-4
Oil Pressure Gage ..........................................3-6
Wait to Start Light ..........................................3-7
Reduced Engine Power Light (Van Models Only) ...3-7
Fuel Gage .....................................................3-8
Water in Fuel Warning Light (Van Models Only) .....3-9
Driver Information Center (DIC)
(Pickup Models Only) ....................................3-9
Section 3 Instrument Panel
3-1

Warning Lights, Gages and Indicators
Instrument Panel Cluster
United States Pickup automatic transmission version shown, manual transmission and Canada similar
3-2

Your instrument cluster is designed to let you know at a glance how your vehicle is running. You’ll know how fast you’re
going, about how much fuel you have and many other things you’ll need to know to drive safely and economically.
United States Van version shown, Canada similar
3-3

Malfunction Indicator Lamp
Check Engine Light
Your vehicle has a computer which monitors operation
of the fuel, timing, and emission control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the life
of the vehicle, helping to produce a cleaner environment.
The check engine light comes on to indicate when service
is required. Malfunctions often will be indicated by the
system before any problem is apparent. This may prevent
more serious damage to your vehicle. This system is also
designed to assist your service technician in correctly
diagnosing any malfunction.
Notice: If you keep driving your vehicle with this
light on, after awhile, your emission controls may not
work as well, your fuel economy may not be as good,
and your engine may not run as smoothly. This could
lead to costly repairs that may not be covered by
your warranty.
Notice: Modifications made to the engine,
transmission, exhaust, intake, or fuel system of
your vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and may cause this light to come on.
Modifications to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test.
Pickup Models Van Models
3-4

If the Light Comes On
This light should come on, as a check to show you it is
working, when the ignition is on and the engine is not
running. If it does not, have it repaired. This light will also
come on if an emission control system malfunction has
been detected on your vehicle. Diagnosis and service
may be required.
You also may be able to correct the emission system
malfunction by considering the following:
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
Are you low on fuel?
As your engine starts to run out of fuel, your engine may
not run as efficiently as designed since small amounts of
air are sucked into the fuel line. The system can detect
this. Adding fuel should correct this condition. It will take
a few driving trips to turn the light off.
If none of the above steps have made the light turn off,
your dealer can check the vehicle. Your dealer has the
proper test equipment and diagnostic tools to fix any
mechanical or electrical problems that may have
developed.
Emissions Inspection and
Maintenance Programs
Some state/provincial and local governments have or
may begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this inspection
could prevent you from getting a vehicle registration.
Here are some things you need to know in order to help
your vehicle pass an inspection:
Your vehicle will not pass this inspection if the check
engine light is on or not working properly.
Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen if
you have recently replaced your battery or if your battery
has run down. The diagnostic system is designed to
evaluate critical emission control systems during normal
driving. This may take several days of routine driving. If
you have done this and your vehicle still does not pass
the inspection for lack of OBD system readiness, your
GM dealer can prepare the vehicle for inspection.
3-5

Oil Pressure Gage The oil pressure gage shows the engine oil pressure in
psi (pounds per square inch) when the engine is running.
Canadian vehicles indicate pressure in kPa (kilopascals).
Oil pressure may vary under different driving conditions
and oil types. The DURAMAX
®
engine may generate
oil pressure in excess of 80 psi (548 kPa) under certain
conditions, especially in cold temperatures. This is a
normal operating range.
{CAUTION:
Do not keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches fire. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice: Lack of proper engine oil maintenance may
damage the engine. The repairs would not be covered
by your warranty. Always follow the maintenance
schedule in this manual for changing engine oil.
United States
(Pickup Models)
Canada
(Pickup Models)
United States
(Van Models)
Canada
(Van Models)
3-6

Wait to Start Light
Your diesel engine has a
glow plug system to aid in
starting your vehicle.
For pickup models, this light shows that the system is
functioning properly and tells you when the engine is
ready to be started. For van models, an instrument panel
WAIT TO START indicator light shows that the system
is functioning properly and tells you when the engine is
ready to be started.
Your vehicle has a fast warm-up glow plug system. The
wait to start light will illuminate for a considerably shorter
time than most diesel engines due to the rapid heating of
the glow plug system.
For more information, see Starting the Diesel Engine
on page 2-2.
Reduced Engine Power Light
(Van Models Only)
If the reduced engine
power light comes on
while you are driving, the
computer is indicating that
your vehicle has a problem.
You should take your
vehicle in for service soon.
3-7

Fuel Gage When the ignition is on, the fuel gage shows you
approximately how much fuel you have left in your tank.
The gage will first indicate E (empty) before you are out
of fuel, but you should get more fuel as soon as possible.
Listed are four situations you may experience with your
fuel gage:
•At the gas station, the fuel pump shuts off before
the gage reads F (full).
•It takes a little more or less fuel to fill up than the
fuel gage indicated. For example, the gage may
have indicated the tank was half full, but it actually
took a little more or less than half the tank’s
capacity to fill the tank.
•The gage moves a little when you turn a corner or
speed up.
•The gage doesn’t go back to E (empty) when you
turn off the ignition.
None of these indicate a problem with the fuel gage.
For information on how to fill your fuel tank, see
Filling the Tank on page 5-15.
Your vehicle also has a fuel cooler. To clean,
powerwash the bottom of the vehicle.
Pickup Models,
United States
version shown
Pickup Models,
Canada
version shown
Van Models
3-8