2009 CHEVROLET TAHOE service

This vehicle has an airbag system. Before attempting
to do your own service work, seeServicing Your
Airbag-Equipped Vehicle on page 1-96.
Keep a record with all parts receipts and list the mileage
and the date of any service work performed. See
Maintenance Record on page 6-17.
Adding Equipment to the Outside of
the Vehicle
Things added to the outside of the vehicle can affect the
airow around it. This can cause wind noise and can
affect fuel economy and windshield washer performance.
Check with your dealer/retailer before adding equipment
to the outside of the vehicle.
Fuel
Use of the recommended fuel is an important part of the
proper maintenance of this vehicle. To help keep the
engine clean and maintain optimum vehicle performance,
we recommend the use of gasoline advertised as TOP
TIER Detergent Gasoline.
The 8th digit of the Vehicle Identication Number (VIN)
shows the code letter or number that identies the
vehicle’s engine. The VIN is at the top left of the
instrument panel. SeeVehicle Identification Number
(VIN) on page 5-113.If the vehicle has the 5.3L V8 engine (VIN Code 0), the
5.3L V8 engine (VIN Code 3), or the 6.2L V8 engine
(VIN Code 2–), you can use either unleaded gasoline or
ethanol fuel containing up to 85% ethanol (E85). See
Fuel E85 (85% Ethanol) on page 5-7. In all other
engines, use only unleaded gasoline. SeeGasoline
Octane on page 5-5.
Gasoline Octane
For all vehicles except those with the 6.2L V8 engine
(VIN Code 2), use regular unleaded gasoline with
a posted octane rating of 87 or higher. If the octane
rating is less than 87, you might notice an audible
knocking noise when you drive, commonly referred to
as spark knock. If this occurs, use a gasoline rated at
87 octane or higher as soon as possible. If you are using
gasoline rated at 87 octane or higher and you hear
heavy knocking, the engine needs service.
If the vehicle has the 6.2L V8 engine (VIN Code 2), use
premium unleaded gasoline with a posted octane rating
of 91 or higher. You can also use regular unleaded
gasoline rated at 87 octane or higher, but the vehicle’s
acceleration could be slightly reduced, and you might
notice a slight audible knocking noise, commonly referred
to as spark knock. If the octane is less than 87, you
might notice a heavy knocking noise when you drive.
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If this occurs, use a gasoline rated at 87 octane or higher
as soon as possible. Otherwise, you could damage the
engine. If you are using gasoline rated at 87 octane or
higher and you hear heavy knocking, the engine needs
service.
Gasoline Specications
At a minimum, gasoline should meet ASTM specication
D 4814 in the United States or CAN/CGSB-3.5 or 3.511 in
Canada. Some gasolines contain an octane-enhancing
additive called methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend against the use of
gasolines containing MMT. SeeAdditives on page 5-6for
additional information.
California Fuel
If the vehicle is certied to meet California Emissions
Standards, it is designed to operate on fuels that meet
California specications. See the underhood emission
control label. If this fuel is not available in states adopting
California emissions standards, the vehicle will operate
satisfactorily on fuels meeting federal specications, but
emission control system performance might be affected.
The malfunction indicator lamp could turn on and the
vehicle might fail a smog-check test. SeeMalfunction
Indicator Lamp on page 3-43. If this occurs, return to yourauthorized dealer/retailer for diagnosis. If it is determined
that the condition is caused by the type of fuel used,
repairs might not be covered by the vehicle warranty.
Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that help prevent
engine and fuel system deposits from forming, allowing
the emission control system to work properly. In most
cases, you should not have to add anything to the fuel.
However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. To help keep fuel injectors
and intake valves clean, or if the vehicle experiences
problems due to dirty injectors or valves, look for gasoline
that is advertised as TOP TIER Detergent Gasoline.
For customers who do not use TOP TIER Detergent
Gasoline regularly, one bottle of GM Fuel System
Treatment PLUS, added to the fuel tank at every engine
oil change, can help clean deposits from fuel injectors
and intake valves. GM Fuel System Treatment PLUS is
the only gasoline additive recommended by General
Motors.
Also, your dealer/retailer has additives that will help
correct and prevent most deposit-related problems.
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Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines might be available in
your area. We recommend that you use these gasolines,
if they comply with the specications described earlier.
However, E85 (85% ethanol) and other fuels containing
more than 10% ethanol must not be used in vehicles that
were not designed for those fuels.
Notice:This vehicle was not designed for fuel
that contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in the fuel
system and also damage plastic and rubber parts.
That damage would not be covered under the vehicle
warranty.
Some gasolines that are not reformulated for low
emissions can contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. We recommend against
the use of such gasolines. Fuels containing MMT can
reduce the life of spark plugs and the performance of
the emission control system could be affected. The
malfunction indicator lamp might turn on. If this occurs,
return to your dealer/retailer for service.Fuel E85 (85% Ethanol)
The 8th digit of the Vehicle Identication Number (VIN)
shows the code letter or number that identies the
vehicle’s engine. The VIN is at the top left of the
instrument panel. SeeVehicle Identification Number
(VIN) on page 5-113.
If the vehicle has the 5.3L V8 engine (Code 0), the
5.3L V8 engine (Code 3), or the 6.2L V8 engine (Code 2),
you can use either unleaded gasoline or ethanol fuel
containing up to 85% ethanol (E85). SeeFuel on
page 5-5. In all other engines, use only the unleaded
gasoline described underGasoline Octane on page 5-5.
Only vehicles that have the 5.3L V8 engine (Code 0), the
5.3L V8 engine (Code 3), or the 6.2L V8 engine (Code 2)
can use 85% ethanol fuel (E85). We encourage the use
of E85 in vehicles that are designed to use it. The ethanol
in E85 is a “renewable” fuel, meaning it is made from
renewable sources such as corn and other crops.
Many service stations will not have an 85% ethanol
fuel (E85) pump available. The U. S. Department
of Energy has an alternative fuels website
(www.eere.energy.gov/afdc/infrastructure/locator.html)
that can help you nd E85 fuel. Those stations that
do have E85 should have a label indicating ethanol
content. Do not use the fuel if the ethanol content
is greater than 85%.
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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 ushes 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 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 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 3-64. Change
the oil as soon as possible within the next 600 miles
(1 000 km). 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 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, the oil must be
changed at 3,000 miles (5 000 km) since the last oil
change. Remember to reset the oil life system whenever
the oil is changed.
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Automatic Transmission Fluid
(6-Speed Transmission)
When to Check and Change Automatic
Transmission Fluid
It is usually not necessary to check the transmission uid
level. The only reason for uid loss is a transmission leak
or overheating the transmission. If you suspect a small
leak, then use the following checking procedures to check
the uid 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.
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 6-13.Change the uid and lter at the intervals listed in the
Maintenance Schedule. SeeScheduled Maintenance on
page 6-4. Be sure to use the transmission uid listed
inRecommended Fluids and Lubricants on page 6-13.
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 the vehicle as
follows:
1. Start the engine and park the vehicle on a level
surface. Keep the engine running.
2. Apply the parking brake and place the shift lever
in P (Park).
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5. Safe operating level is within the HOT cross hatch
band on the dipstick. If the uid level is not within the
HOT band, and the transmission temperature is
between 160°F and 200°F (71°C and 93°C), add or
drain uid as necessary to bring the level into the
HOT band. If the uid level is low, add only enough
uid to bring the level into the HOT band. It does not
take much uid, generally less than one pint (0.5L).
Do not overll.
6. If the uid level is in the acceptable range, push the
dipstick back in all the way, then ip the handle
down to lock the dipstick in place.
Consistency of Readings
Always check the uid level at least twice using the
procedure described previously. Consistency (repeatable
readings) is important to maintaining proper uid level. If
readings are still inconsistent, contact your dealer/retailer.
Automatic Transmission Fluid
(4-Speed Transmission)
When to Check and Change Automatic
Transmission Fluid
A good time to check the 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 6-6and 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
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 uid 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 uid 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 in 3 (Third) until the engine temperature
gage moves and then remains steady for 10 minutes.
A cold uid 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
ve 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 uid level be low during
this cold check, you must check the uid hot before
adding uid. Checking the uid hot will give you a more
accurate reading of the uid level.
Checking the Fluid Level
Prepare the vehicle as follows:
1. Park the vehicle on a level place. Keep the engine
running.
2. With the parking brake applied, 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, position
the shift lever in P (Park).
4. Let the engine run at idle for three minutes or more.
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In addition, ENGINE OVERHEATED STOP ENGINE,
ENGINE OVERHEATED IDLE ENGINE, and a ENGINE
POWER IS REDUCED message comes on in the
Driver Information Center (DIC) on the instrument panel.
SeeDIC Warnings and Messages on page 3-64.
You may decide not to lift the hood when this warning
appears, but instead get service help right away.
SeeRoadside Assistance Program on page 7-7.
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.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
Overheated Engine Protection Operating Mode on
page 5-36for information on driving to a safe place
in an emergency.
Notice:If the engine catches re while driving
with no coolant, the vehicle can be badly damaged.
The costly repairs would not be covered by the
vehicle warranty. SeeOverheated Engine Protection
Operating Mode on page 5-36for information on
driving to a safe place in an emergency.If Steam Is Coming From The Engine
Compartment
{CAUTION:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see or hear steam coming
from it. Turn it off and get everyone away from
the vehicle until it cools down. Wait until there
is no sign of steam or coolant before you open
the hood.
If you keep driving when the vehicles engine is
overheated, the liquids in it can catch re. You or
others could be badly burned. Stop the engine if it
overheats, and get out of the vehicle until the
engine is cool.
SeeOverheated Engine Protection Operating
Mode on page 5-36for information on driving to a
safe place in an emergency.
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