
5. For van models, in order to drain the water from the
system, you will have to repeat the operation for the
primary and secondary fuel filters.6. Remove the fuel-resistant container and properly
dispose of the contaminated fuel. To find out how
to properly dispose of contaminated diesel fuel,
see “What to Do With Used Oil” underEngine Oil
on page 5-21.
7. Install the fuel cap.
8. For pickup models, start the engine and let it run for a
few minutes. If the engine stalls, the fuel system may
need to be primed. While draining the water from the
fuel filter, air may enter the fuel system. If air has
entered the fuel system the fuel system will need to
be primed. For van models, start the engine and let it
run for a few minutes.
If the WATER IN FUEL message/warning light comes
on again after driving a short distance or the engine runs
rough or stalls, a large amount of water has probably
been pumped into the fuel tank. The fuel tank should
be purged.
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5. Open the fuel filter vent
valve by turning the
screw counterclockwise
several full turns. The
vent valve is located
on top of the fuel filter
housing.
6. Repeatedly push down
on the fuel filter priming
pump with the palm of
your hand. The pump
is located on top of the
fuel filter housing. Let
the pump return upward
between pushes.7. Operate the priming pump until a small amount of
fuel seeps from the vent valve. When you see the
fuel, the filter is now full of fuel and the system
should be primed.
8. Close the vent valve. Clean any fuel which
accumulated on the fuel filter. Start the engine and
let idle for a few minutes. Check the filter for leaks.
Q:How do I prime the vehicle? (Van Models)
A:Your vehicle is equipped with an electric priming
pump which is located in front of the fuel tank
under your vehicle. The priming pump is operated
electrically and is designed to bring fuel to the engine
to eliminate any air that may be in the fuel lines.
To prime the engine, do the following:
1. Turn the ignition key on for two minutes. The fuel
pump will be operating and starting the priming
process. Do not start the engine during the first
two minutes.
2. After completing the initial prime in Step 1, turn the
ignition off, then back to start and crank the engine
for 15 seconds.
3. If the engine does not start, repeat Steps 1 and 2
until the engine starts.
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4. If the engine does not run after repeating Steps 1
and 2 three times, turn the ignition key off for
60 seconds, allowing the Electronic Control
Module (ECM) to reset.
5. Repeat the above steps until the engine starts.
6. If the engine runs, but does not run smoothly,
increase the engine speed slightly by pressing
the accelerator pedal. This will help to force
out air through the system.
7. If the engine starts and runs but stalls again, turn the
ignition key off for 60 seconds to reset the ECM and
repeat the steps above.
8. When the engine starts, let it idle for a few minutes
and check the filters for any leaks.Running Out of Fuel
Pickup Models
If the engine stalls and you think that you have run out
of fuel, do this to restart your engine:
{CAUTION:
Diesel fuel is ammable. It could start a re if it
gets on hot engine parts. You could be burned.
Do not let too much fuel ow from the air bleed
valve, and wipe up any spilled fuel with a cloth.
1. If you are parked on a level surface, add at least
two gallons of fuel. However, if you are parked on a
slope, you may need to add up to five gallons of fuel.
2. Follow the fuel priming procedure earlier in this
section to prime the fuel filter.
3. Close the air bleed valve.
4. Turn the ignition key to START for 10 to 15 seconds
at a time until your engine starts. If the engine tries to
run, but does not run smoothly, increase the rpm a
little using the accelerator pedal. This will help force
air through the system.
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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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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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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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How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission fluid to use. SeeRecommended
Fluids and Lubricants on page 6-15.
Using a funnel, add fluid down the transmission dipstick
tube only after checking the transmission fluid while it is
hot. A cold check is used only as a reference. If the fluid
level is low, add only enough of the proper fluid to bring
the level up to the HOT area for a hot check. It does not
take much fluid, generally less than one pint (0.5L). Do
not overfill.
Notice:Use of the incorrect automatic transmission
uid may damage your vehicle, and the damages
may not be covered by your warranty. Always
use the automatic transmission uid listed in
Recommended Fluids and Lubricants on page 6-15.
•After adding fluid, recheck the fluid level as
described under “How to Check” earlier in
this section.
•When the correct fluid level is obtained, push the
dipstick back in all the way. Then flip the handle
down to lock the dipstick in place.
Engine Coolant
Pickup Models
The cooling system in your vehicle is filled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs first, if you add only
DEX-COOL
®extended life coolant.
The following explains your cooling system and how
to add coolant when it is low. If you have a problem
with engine overheating, seeEngine Overheating
on page 5-39.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
•Give freezing protection down to−34°F (−37°C)
•Give boiling protection up to 265°F (129°C)
•Protect against rust and corrosion
•Help keep the proper engine temperature
•Let the warning lights and gages work as they should
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at the rst maintenance
service after each 30,000 miles (50 000 km) or
24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
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Adding Coolant
If you need more coolant, add the proper DEX-COOL®
coolant mixtureat the coolant recovery tank, but be
careful not to spill it.
{CAUTION:
You can be burned if you spill coolant on hot
components in the engine compartment.
Coolant contains ethylene glycol, and it will
burn if the engine parts are hot enough. Do not
spill coolant on a hot engine or components in
the engine compartment.
When replacing the pressure cap, make sure it is
hand-tight.
Radiator Pressure Cap
The radiator pressure cap must be tightly installed.
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
Coolant Surge Tank Pressure Cap
The surge tank pressure
cap must be tightly
installed.
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
Engine Overheating
You will find an engine coolant temperature gage on the
instrument panel cluster. For pickup models, the ENGINE
OVERHEATED message may appear in the Driver
Information Center (DIC). See your owner’s manual for
more information.
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