2008 CHEVROLET TAHOE reset

If you are in an area of extreme cold, where the
temperature falls below−20°F (−29°C), it is
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both provide easier
cold starting and better protection for the engine at
extremely low temperatures.
Engine Oil Additives
Do not add anything to the oil. The recommended oils
with the starburst symbol that meet GM Standard
GM6094M are all you 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 lter. This is based
on engine revolutions and engine temperature, and not
on mileage. Based on driving conditions, the mileage
at which an 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 SOON message will come on.
SeeDIC Warnings and Messages on page 3-59. Change
the 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 might not indicate that
an oil change is necessary for over a year. However, the
engine oil and lter 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, you must
change the 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.
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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 lter 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 you change the oil prior to a CHANGE ENGINE
OIL SOON message coming on, reset the system.
Always reset the engine oil life to 100% after every oil
change. It will not reset itself. To reset the Engine
Oil Life System:
1. Display the OIL LIFE REMAINING on the DIC.
If your vehicle does not have DIC buttons, the
vehicle must be in PARK (P) to access this display.
SeeDIC Operation and Displays (With DIC
Buttons) on page 3-51orDIC Operation and
Displays (Without DIC Buttons) on page 3-56.
2. Press and hold the SET/RESET button on the DIC,
or the trip odometer reset stem if your vehicle does
not have DIC buttons, for more than ve seconds.
The oil life will change to 100%.
If the CHANGE ENGINE OIL SOON message comes
back on when you start your vehicle, the Engine Oil Life
System has not reset. Repeat the procedure.
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 lter 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. Instead, recycle it
by taking it to a place that collects used oil. If you have
a problem properly disposing of used oil, ask your
dealer/retailer, a service station, or a local recycling
center for help.
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Engine Air Cleaner/Filter
SeeEngine Compartment
Overview on page 5-16for
the location of the engine
air cleaner/lter and the air
lter restriction indicator,
if the vehicle has one.
When to Inspect the Engine Air
Cleaner/Filter
If your vehicle has an air lter restriction indicator, it lets
you know when the engine air cleaner/lter needs to be
replaced. On vehicles with a restriction indicator, you
should inspect the air lter restriction indicator at every oil
change and replace the engine air cleaner/lter when the
indicator tells you to.On vehicles without an air lter restriction indicator,
inspect the air cleaner/lter at the MaintenanceII
intervals and replace it at the rst oil change after
each 50,000 mile (80 000 km) interval. SeeScheduled
Maintenance on page 6-4for more information.
If you are driving in dusty/dirty conditions, inspect
the lter at each engine oil change.
How to Inspect the Engine Air
Cleaner/Filter
Vehicles With an Air Filter Restriction
Indicator
Locate the air lter restriction indicator on the engine air
cleaner/lter cover. When the indicator turns black or
is in the red/orange “change” zone, replace the lter and
reset the indicator. See the steps following to replace
the engine air cleaner/lter and to reset the air lter
restriction indicator.
Vehicles Without an Air Filter Restriction
Indicator
To inspect the air cleaner/lter, remove the engine air
cleaner/lter from the vehicle by following Steps 1
through 6. When you have the engine air cleaner/lter
removed, lightly shake it to release loose dust and dirt.
If the engine air cleaner/lter remains caked with
dirt, a new lter is required.
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Replacing the Engine Air Cleaner/Filter
and Resetting the Air Filter Restriction
Indicator
1. Locate the air cleaner/
lter assembly. See
Engine Compartment
Overview on
page 5-16.
2. Loosen the four screws on the cover of the housing
and lift up the cover.3. Remove the engine air cleaner/lter from the
housing. Care should be taken to dislodge as
little dirt as possible.
4. Clean the engine air cleaner/lter sealing surfaces
and the housing.
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5. Inspect or replace the engine air cleaner/lter.
6. Reinstall the cover and tighten the screws.
7. Reset the air lter restriction indicator, if the vehicle
has one, by pressing the top button on the indicator.
{CAUTION:
Operating the engine with the air cleaner/lter
off can cause you or others to be burned.
The air cleaner not only cleans the air; it helps
to stop ames if the engine backres. If it is
not there and the engine backres, you could
be burned. Do not drive with it off, and be
careful working on the engine with the air
cleaner/lter off.
Automatic Transmission Fluid
(4-Speed Transmission)
When to Check and Change Automatic
Transmission Fluid
A good time to check your automatic transmission uid
level is when the engine oil is changed.
Change the uid and lter at the intervals listed in
Additional Required Services on page 6-6, and be sure
to use the transmission uid listed inRecommended
Fluids and Lubricants on page 6-13.
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How to Check Automatic Transmission
Fluid
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.
Before checking the uid level, prepare your vehicle as
follows:
1. Start the engine and park your vehicle on a level
surface. Keep the engine running.
2. Apply the parking brake and place the shift lever in
P (PARK).3. With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, move the
shift lever back to P (PARK).
4. Allow the engine to idle (500 – 800 rpm) for at least
one minute. Slowly release the brake pedal.
5. Keep the engine running and press the Trip/Fuel
button or trip odometer reset stem until TRANS
TEMP (Transmission Temperature) displays on
the Driver Information Center (DIC).
6. Using the TRANS TEMP reading, determine and
perform the appropriate check procedure. If the
TRANS TEMP reading is not within the required
temperature ranges, allow the vehicle to cool,
or operate the vehicle until the appropriate
transmission uid temperature is reached.
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If you get the ENGINE OVERHEATED STOP ENGINE
or the ENGINE OVERHEATED IDLE ENGINE message
with no sign of steam, try this for a minute or so:
1. If the vehicle has an air conditioner and it is on,
turn it off.
2. Turn on the heater to the highest temperature and
at the highest fan speed and open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (Neutral)
while stopped. If it is safe to do so, pull off the
road, shift to P (Park) or N (Neutral) and let
the engine idle.
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle immediately.
If there is still no sign of steam and your vehicle has an
engine-driven cooling fan, push down the accelerator
until the engine speed is about twice as fast as normal
idle speed for at least ve minutes while parked.
If there is still no sign of steam and your vehicle has an
electric cooling fan, idle the engine for ve minutes
while parked.If you still have the warning, turn off the engine and get
everyone out of the vehicle until it cools down. Also,
see “Overheated Engine Protection Operating Mode”
later in this section.
You might decide not to lift the hood but to get service
help right away.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
ENGINE POWER IS REDUCED message is displayed,
an overheat protection mode which alternates ring
groups of cylinders helps prevent engine damage.
In this mode, you will notice a loss in power and engine
performance. This operating mode allows your vehicle
to be driven to a safe place in an emergency. Driving
extended miles (km) and/or towing a trailer in the
overheat protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any
repair. The engine oil will be severely degraded.
Repair the cause of coolant loss, change the oil
and reset the oil life system. SeeEngine Oil
on page 5-17.
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What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeeRecommended Fluids
and Lubricants on page 6-13.
Headlamp Aiming
The vehicle has a visual optical headlamp aiming
system. The aim of the headlamps have been preset at
the factory and should need no further adjustment.
However, if the vehicle is damaged in a crash, the aim
of the headlamps can be affected and adjustment
can be necessary.
If oncoming vehicles ash their high beams at you, this
can mean the vertical aim of your headlamps needs
to be adjusted.
It is recommended that the vehicle is taken to your
dealer/retailer for service if the headlamps need to
be adjusted. It is possible however, to re-aim the
headlamps as described.The vehicle should:
Be placed so the headlamps are 25 ft. (7.6 m) from
a light colored wall.
Have all four tires on a level surface which is level
all the way to the wall.
Be placed so it is perpendicular to the wall.
Not have any snow, ice, or mud on it.
Be fully assembled and all other work stopped while
headlamp aiming is being performed.
Be normally loaded with a full tank of fuel and one
person or 160 lbs (75 kg) sitting on the driver seat.
Have tires properly inated.
Have the spare tire is in its proper location in the
vehicle.
Headlamp aiming is done with the vehicle’s low-beam
headlamps. The high-beam headlamps will be correctly
aimed if the low-beam headlamps are aimed properly.
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