2007 CHEVROLET EXPRESS service

Engine Oil Additives / Engine Oil
Flushes
Do not add anything to the oil. The recommended
oils with the starburst symbol that meet GM Standard
GM6094M are all that is needed for good performance
and engine protection.
Engine oil system flushes are not recommended and
could cause engine damage not covered by the vehicle
warranty.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that indicates when
to change the engine oil and filter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change is indicated can vary considerably.
For the oil life system to work properly, the system
must be reset every time the oil is changed.When the system has calculated that oil life has been
diminished, it indicates that an oil change is necessary.
A CHANGE ENGINE OIL SOON message comes on.
SeeDIC Warnings and Messages on page 4-44. Change
the oil as soon as possible within the next 1 000 km
(600 miles). It is possible that, if driving under the best
conditions, the oil life system might not indicate that an oil
change is necessary for over a year. However, the engine
oil and filter must be changed at least once a year and at
this time the system must be reset. Your dealer/retailer
has trained service people who will perform this work
using genuine parts and reset the system. It is also
important to check the oil regularly and keep it at the
proper level.
If the system is ever reset accidentally, the oil must be
changed at 5 000 km (3,000 miles) since the last oil
change. Remember to reset the oil life system whenever
the oil is changed.
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How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to change
the engine oil and filter based on vehicle use. Whenever
the oil is changed, reset the system so it can calculate
when the next oil change is required. If a situation occurs
where the oil is changed prior to a CHANGE ENGINE OIL
SOON message being turned on, reset the system.
To reset the CHANGE ENGINE OIL SOON message:
1. Turn the ignition key to ON/RUN with the engine off.
2. Fully press and release the accelerator pedal
slowly three times within five seconds.
3. Turn the key to LOCK/OFF.
If the message comes back on when the vehicle
is started, the engine oil life system has not reset.
Repeat the procedure. If it still does not reset, see
your dealer/retailer for service.
What to Do with Used Oil
Used engine oil contains certain elements that can be
unhealthy for your skin and could even cause cancer.
Do not let used oil stay on your skin for very long. Clean
your skin and nails with soap and water, or a good
hand cleaner. Wash or properly dispose of clothing or
rags containing used engine oil. See the manufacturer’s
warnings about the use and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from the
filter before disposal. Never dispose of oil by putting it
in the trash, pouring it on the ground, into sewers, or into
streams or bodies of water. Recycle it by taking it to a
place that collects used oil.
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How to Check Automatic Transmission
Fluid
Because this operation can be a little difficult, you may
choose to have this done at the dealer/retailer 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
parts 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 32°C (90°F).
•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 82°C to 93°C
(180°F to 200°F).
Get the vehicle warmed up by driving about 24 km
(15 miles) when outside temperatures are above 10°C
(50°F). If it is colder than 10°C (50°F), drive the vehicle in
D (DRIVE) until the engine temperature gage moves and
then remains steady for 10 minutes.
A cold fluid 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 10°C (50°F), 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 Automatic Transmission
Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission fluid to use. SeeRecommended
Fluids and Lubricants on page 7-12.
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 (0.5 L).
Do not overfill.
Notice:Use of the incorrect automatic transmission
uid may damage the vehicle, and the damages may
not be covered by the vehicle’s warranty. Always
use the automatic transmission uid listed in
Recommended Fluids and Lubricants on page 7-12.
•After adding fluid, recheck the fluid level as described
under “How to Check Automatic Transmission Fluid,”
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.
Automatic Transmission Fluid
(6-Speed Transmission)
When to Check and Change Automatic
Transmission Fluid
It is usually not necessary to check the transmission fluid
level. The only reason for fluid loss is a transmission
leak or overheating the transmission. If a small leak is
suspected, use the following procedures to check the
fluid level. However, if there is a large leak, then it may be
necessary to have the vehicle towed to a dealer/retailer
service department and have it repaired before driving
the vehicle further.
Change the fluid and filter at the intervals listed in
Scheduled Maintenance on page 7-3, and be sure
to use the transmission fluid listed inRecommended
Fluids and Lubricants on page 7-12.
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How to Check Automatic Transmission
Fluid
Because this operation can be difficult, it is recommended
to have this check done at the dealer/retailer service
department, which can monitor the transmission
temperature. The transmission fluid level increases
with temperature. To obtain a highly accurate fluid level
check, the transmission temperature must be measured.
If it is decided to check the fluid level, be sure to follow
all the instructions here, or a false reading on the
dipstick may occur.
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
parts 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 with the engine Off, before
checking the transmission fluid level if the vehicle has
been driven:
•In hot weather, when outside temperatures are
above 32°C (90°F).
•The vehicle is heavily loaded.
•At high speed for quite a while in hot weather.
•In heavy traffic and hot weather.
•While pulling a trailer.
After driving under these conditions, a hot check can
be performed. The fluid should be Hot, which is
71°C to 93°C (160°F to 200°F).
A cold fluid level check can be performed 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 is
between 15°C to 32°C (60°F to 90°F). Should the fluid
level be low during this cold check, the fluid must be
checked Warm or Hot before adding fluid. If the outside
temperature is colder than 15°C (60°F) or hotter than
32°C (90°F), a cold check cannot be performed.
A warm fluid level check can be performed by driving
the vehicle under lightly loaded conditions and outside
temperatures between 10°C to 27°C (50°F to 80°F).
The vehicle should be driven for at least 15 miles before
performing a warm check. Checking the fluid Warm or
Hot will give a more accurate reading of the fluid level
than a cold check.
Because the vehicle is equipped with a high-efficiency
air-to-oil cooler, the transmission fluid temperature
may not reach the required Hot fluid level checking
temperature under normal lightly loaded driving vehicle
conditions.
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Checking Coolant
The vehicle must be on a level surface when checking
the coolant level.
Check to see if coolant is visible in the coolant recovery
tank. If the coolant inside the coolant recovery tank is
boiling, do not do anything else until it cools down.
If coolant is visible but the coolant level is not at or above
the COLD FILL mark, add a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant at the coolant
recovery tank, but be sure the cooling system is cool
before this is done.
When the engine is cold, the coolant level should be at
or above the COLD FILL mark. If it is not, there could
be a leak in the cooling system.
If the coolant is low, add the coolant or take the vehicle
to a dealer/retailer for service.
How to Add Coolant to the Recovery
Tank for Gasoline Engines
If your vehicle has a diesel engine, see “How to
Add Coolant to the Coolant Recovery Tank” under
“Van Models” in the Cooling System section of the
DURAMAX
®Diesel Supplement for the proper coolant
fill procedure.
{WARNING:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot enough.
Do not spill coolant on a hot engine.
Notice:This vehicle has a specic coolant ll
procedure. Failure to follow this procedure could
cause the engine to overheat and be severely
damaged.
If coolant is needed, add the proper DEX-COOL
®
coolant mixture at the coolant recovery tank.
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7. By this time, the coolant level inside the radiator
filler neck may be lower. If the level is lower, add
more of the proper DEX-COOL
®coolant mixture
through the filler neck until the level reaches
the base of the filler neck.
8. Then replace the pressure cap. At any time during
this procedure if coolant begins to flow out of the
filler neck, reinstall the pressure cap.
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
If your vehicle has the DURAMAX Diesel engine, see
the DURAMAX Diesel manual for more information.
The vehicle has an indicator to warn of engine
overheating.
You will find an engine coolant temperature gage on
your vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 4-29for more information.You may decide not to lift the hood when this warning
appears, but instead get service help right away.
SeeRoadside Assistance Program on page 8-8.
If you do decide to lift the hood, make sure the vehicle
is parked on a level surface.
Then check to see if the engine cooling fans are
running. If the engine is overheating, both fans should
be running. If they are not, do not continue to run
the engine and have the vehicle serviced.
See if the engine cooling fan speed increases when idle
speed is doubled by pushing the accelerator pedal down.
If it does not, your vehicle needs service. Turn off the
engine.
Notice:Engine damage from running the engine
without coolant is not covered by the warranty.
Notice:If the engine catches re because of being
driven with no coolant, your vehicle can be badly
damaged. The costly repairs would not be covered
by the vehicle warranty.
6-35

If the temperature overheat gage is no longer in the
overheat zone or an overheat warning no longer
displays, the vehicle can be driven. Continue to drive
the vehicle slow for about 10 minutes. Keep a safe
vehicle distance from the car in front of you. If the
warning does not come back on, continue to drive
normally.
If the warning continues, pull over, stop, and park the
vehicle right away.
If there is still no sign of steam, push down the
accelerator until the engine speed is about twice
as fast as normal idle speed for at least three minutes
while you are parked. If you still have the warning,
turn off the engine until it cools down.
You may decide not to lift the hood but to get service
help right away.Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When the
clutch is engaged, the fan spins faster to provide more air
to cool the engine. In most everyday driving conditions,
the fan is spinning slower and the clutch is not fully
engaged. This improves fuel economy and reduces fan
noise. Under heavy vehicle loading, trailer towing, and/
or high outside temperatures, the fan speed increases
as the clutch more fully engages, so you may hear an
increase in fan noise. This is normal and should not be
mistaken as the transmission slipping or making extra
shifts. It is merely the cooling system functioning properly.
The fan will slow down when additional cooling is not
required and the clutch partially disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch partially
disengages.
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