
Van Models
If the engine stalls and you think that you may have run
out of fuel, do this to restart your engine:
1. If you are parked on a level surface, add at least
one gallon of fuel. However, if you are parked on a
slope, you may need to add up to five gallons of fuel.
2. Follow the vehicle fuel system priming procedure
earlier in this section to re-prime the system and
re-start the engine.
Your check engine light may come on if the vehicle has
run out of fuel. This light may stay on for a few drive
cycles after the condition is corrected, but will eventually
clear itself.
Fuel Filter Replacement
Pickup Models
If you want to change the fuel filter yourself, here’s how
to do it:
{CAUTION:
Diesel fuel is ammable. It could start a re if
something ignites it, and you could be burned.
Do not let it get on hot engine parts, and keep
matches or other ignition sources away.
First, drain any water from the filter following the
procedure for draining water listed previously.
Your vehicle’s engine should be off until the end of this
procedure.
The fuel filter is located in the engine compartment on
the passenger’s side of the vehicle, or on the driver’s
side frame rail in front of the fuel tank.
1. Apply the parking brake.
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2. Unplug the water
sensor wire connected
to the fuel filter and
unscrew the filter
element.
3. Remove the filter element. If there is any dirt on the
filter sealing surface, clean it off. Remove and reuse
the water sensor float switch located on the bottom of
the fuel filter.
4. Install the new filter element.
5. Reinstall and tighten the filter container and
reconnect the water sensor wire to the filter.
6. Use the fuel filter priming procedure earlier in this
section to prime the fuel filter.
7. Tighten the air bleed valve by turning it clockwise
until hand tight.
8. Start your engine and let it idle for five minutes.
Check your fuel filter and air bleed valve for leaks.9. Reset the fuel filter monitor. SeeDriver Information
Center (DIC) (Pickup Models Only) on page 3-9for
more information.
Van Models
If your fuel operated heater (FOH) is not working, your
FOH line requires priming. See your dealer for service.
SeeFuel Operated Heater (FOH) (Van Models Only) on
page 2-8for more information.
If you want to change the fuel filter yourself, here’s how
to do it:
{CAUTION:
Diesel fuel is ammable. It could start a re if
something ignites it, and you could be burned.
Do not let it get on hot engine parts, and keep
matches or other ignition sources away.
First, drain any water from the filter following the
procedure for draining water listed previously.
Your vehicle’s engine should be off until the end of this
procedure.
The fuel filters are located on the driver’s side frame rail
in front of the fuel tank.
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Checking Things Under the Hood
Engine Compartment Overview
When you open the hood on the 6.6L DURAMAX®Diesel Engine, you’ll see:
United States pickup models shown, Canada similar
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A. Battery
B. Coolant Surge Tank
C. Automatic Transmission Dipstick
D. Engine Fan
E. Engine Air Cleaner/Filter
F. Engine Oil Fill Cap
G. Power Steering Fluid Reservoir
H. Brake Fluid Reservoir
I. Windshield Washer Fluid Reservoir
Engine Oil
Checking Engine Oil
It is a good idea to check your engine oil level every
time you get fuel.
The engine oil dipstick handle is a yellow loop.
SeeEngine Compartment Overview on page 5-18
for the location of the engine oil dipstick.In order to get an accurate reading, the oil must be
warm, at normal operating temperature, and the vehicle
must be on level ground.
1. Turn off the engine and give the oil at least
five minutes to drain back into the oil pan. With a
cool engine, allow 30 minutes. If you do not do this,
the oil dipstick might not show the actual level.
2. Pull out the dipstick and clean it with a paper towel
or a cloth, then push it back in all the way. Remove
it again, keeping the tip down.
When to Add Engine Oil
If the oil is below the cross-hatched area at the tip of the
dipstick, you will need to add at least two quarts/liters of
oil. But you must use the right kind. This section explains
what kind of oil to use. For engine oil crankcase capacity,
seeSpeci cation Charts on page 5-50.
Notice:Do not add too much oil. If the engine
has so much oil that the oil level gets above the
cross-hatched area that shows the proper operating
range, the engine could be damaged.
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Engine Oil Additives
Do not add anything to your oil. The recommended oils
with the API service symbol are all you will need for
good performance and engine protection.
Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer system that lets you know
when to change the engine oil and filter. This is based on
engine timing, engine load, and engine temperature, and
not on mileage. Based on driving conditions, the mileage
at which an engine oil change will be indicated can vary
considerably. For the oil life system to work properly, you
must reset the system every time the oil is changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is necessary.
A CHANGE ENGINE OIL message in pickup models
or a change engine oil light in van models will come on.
Change your oil as soon as possible within the next
600 miles (1 000 km). It is possible that, if you are driving
under the best conditions, the oil life system may not
indicate that an oil change is necessary for over a year.
However, your engine oil and filter must be changed at
least once a year and at this time the system must be
reset. Your dealer has GM-trained service people who
will perform this work using genuine GM parts and reset
the system. It is also important to check your oil regularly
and keep it at the proper level.If the system is ever reset accidentally, you must
change your oil at 3,000 miles (5 000 km) since your
last oil change. Remember to reset the oil life system
whenever the oil is changed.
How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to change
your engine oil and filter based on vehicle use. Anytime
your oil is changed, reset the system so it can calculate
when the next oil change is required. If a situation occurs
where you change your oil prior to a CHANGE ENGINE
OIL message (pickup models) or a change engine oil light
(van models) being turned on, reset the system.
To reset the Engine Oil Life System, do the following:
1. Turn the ignition key to RUN with the engine off.
2. Fully press and release the accelerator pedal
three times within five seconds.
Pickup Models: If the OIL LIFE RESET message
flashes for 10 seconds, the system is resetting.
Van Models: If the change engine oil light flashes
for five seconds, the system is reset.
3. Turn the key to LOCK.
If the message or light comes back on when you start
your vehicle, the engine oil life system has not reset.
Repeat the procedure. If it still does not reset, see your
dealer for service.
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Automatic Transmission Fluid
When to Check and Change
(Pickup Models)
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change both the fluid and filter every 25,000 miles
(41 500 km) if the vehicle is mainly driven under one
or more of these conditions:
•In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
•In hilly or mountainous terrain.
•When doing frequent trailer towing.
•Uses such as found in taxi, police or
delivery service.
If you do not use your vehicle under any of
these conditions, change the fluid and filter
every 50,000 miles (83 000 km).
SeeScheduled Maintenance on page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too little uid can damage your
transmission. Too much can mean that some of the
uid could come out and fall on hot engine part or
exhaust system parts, starting a re. Too little uid
could cause the transmission to overheat. Be sure
to get an accurate reading if you check your
transmission uid.
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving:
•When outside temperatures are above 90°F (32°C).
•At high speed for quite a while.
•In heavy traffic — especially in hot weather.
•While pulling a trailer.
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Checking the Fluid Level
Prepare your vehicle as follows:
•Park your vehicle on a level place. Keep the
engine running.
•With the parking brake applied, place the shift lever
in PARK (P).
•With your foot on the brake pedal, run the engine
for at least one minute and shift to DRIVE (D).
Then shift to NEUTRAL (N) and then REVERSE (R)
to fill the hydraulic system. Then, put the shift
lever in PARK (P).
•Allow the engine to run at idle (500 – 800 rpm).
Slowly release the brake pedal.Then, without shutting off the engine, follow these steps:
Cold Check Procedure
The purpose of the cold check is to determine if the
transmission has enough fluid to be operated safely until
a hot check can be made. The fluid level rises as fluid
temperature increases. DO NOT fill above the COLD
CHECK band if the transmission fluid is below normal
operating temperatures.
1. Pull out the dipstick and wipe it with a clean rag or
paper towel. The transmission dipstick is located
near the center of the engine compartment. See
Engine Compartment Overview on page 5-18for
more information on location.
2. Push it back in all the way, wait three seconds and
then pull it back out again.
3. Check the fluid level reading. Repeat the check
procedure to verify the reading.
4. If the fluid level is within the COLD CHECK band, the
transmission may be operated until the fluid is hot
enough to perform a hot check. If the fluid level is not
within the COLD CHECK band, add or drain fluid as
necessary to bring the level into the middle of the
COLD CHECK band.
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When to Check and Change
(Van Models)
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change the fluid and filter at the intervals listed in
“Additional Required Services”. SeeAdditional
Required Services on page 6-7.
And be sure to use the transmission fluid listed
in “Recommended Fluids and Lubricants”. See
Recommended Fluids and Lubricants on page 6-15
for more information.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too little uid can damage your
transmission. Too much can mean that some of the
uid could come out and fall on hot engine part or
exhaust system parts, starting a re. Too little uid
could cause the transmission to overheat. Be sure
to get an accurate reading if you check your
transmission uid.Wait at least 30 minutes before checking the
transmission fluid level if you have been driving:
•When outside temperatures are above 90°F (32° C).
•At high speed for quite a while.
•In heavy traffic — especially in hot weather.
•While pulling a trailer.
To get the right reading, the fluid should be at normal
operating temperature, which is 180°F to 200°F
(82°C to 93°C). Get the vehicle warmed up by driving
about 15 miles (24 km) when outside temperatures are
above 50°F (10°C). If it is colder than 50°F (10°C), drive
the vehicle until the engine temperature gage moves and
then remains steady for 10 minutes.
A cold check can be made after the vehicle has been
sitting for eight hours or more with the engine off, but this
is used only as a reference. Let the engine run at idle for
five minutes if outside temperatures are 50°F (10°C) or
more. If it is colder than 50°F (10 C), you may have to idle
the engine longer. Should the fluid level be low during this
cold check, you must check the fluid hot before adding
fluid. Checking the fluid hot will give you a more accurate
reading of the fluid level.
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