service HUMMER H2 2009 Repair Manual

Keep a record with all parts receipts and list the
mileage and the date of any service work performed.
SeeMaintenance 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.
This vehicle can use either unleaded gasoline or
ethanol fuel containing up to 85% ethanol (E85).
SeeGasoline Octane on page 5-5and
Fuel E85 (85% Ethanol) on page 5-7.
Gasoline Octane
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. 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.
5-5

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)
This vehicle can use either unleaded gasoline or
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%.
At a minimum, E85 should meet ASTM Specication
D 5798. By denition, this means that fuel labeled E85
will have an ethanol content between 70% and 85%.
Filling the fuel tank with fuel mixtures that do not meet
ASTM specications can affect driveability and could
cause the malfunction indicator lamp to come on.
To ensure quick starts in the wintertime, the E85 fuel
must be formulated properly for your climate according to
ASTM specication D 5798. If you have trouble startingon E85, it could be because the E85 fuel is not properly
formulated for your climate. If this happens, switching to
gasoline or adding gasoline to the fuel tank can improve
starting. For good starting and heater efficiency below
32°F (0°C), the fuel mix in the fuel tank should contain
no more than 70% ethanol. It is best not to alternate
repeatedly between gasoline and E85. If you do switch
fuels, it is recommended that you add as much fuel as
possible — do not add less than three gallons (11 L)
when refueling. You should drive the vehicle immediately
after refueling for at least seven miles (11 km) to allow the
vehicle to adapt to the change in ethanol concentration.
E85 has less energy per gallon than gasoline, so you will
need to rell the fuel tank more often when using E85
than when you are using gasoline. SeeFilling the
Tank on page 5-8.
Notice:Some additives are not compatible with
E85 fuel and can harm the vehicle’s fuel system.
Do not add anything to E85. Damage caused by
additives would not be covered by the vehicle
warranty.
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.
5-7

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 3-56. 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.
5-18

2. Lift the cover upward and set it aside.
3. Pull the air cleaner/lter up and out from the air
cleaner housing. Care should be taken to dislodge
as little dirt as possible.4. Clean the air cleaner/lter sealing surfaces and the
housing.
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 equipped,
by pressing the top button on the indicator.
If the vehicle is not equipped with the air lter
restriction indicator, refer to the Maintenance
Schedule to determine when to replace the engine
air cleaner/lter. SeeAdditional Required Services
on page 6-6.
5-22

{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.
Notice:If the air cleaner/lter is off, a backre can
cause a damaging engine re. And, dirt can easily get
into the engine, which will damage it. Always have
the air cleaner/lter in place when you are driving.
Automatic Transmission Fluid
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.
5-23

The coolant level should be at or above the FULL
COLD mark. If it is not, you may have a leak at the
pressure cap or in the radiator hoses, heater hoses,
radiator, water pump, or somewhere else in the cooling
system.
{CAUTION:
Heater and radiator hoses, and other engine parts,
can be very hot. Do not touch them. If you do, you
can be burned.
Do not run the engine if there is a leak. If you run
the engine, it could lose all coolant. That could
cause an engine re, and you could be burned.
Get any leak xed before you drive the vehicle.
If there seems to be no leak, start the engine again.
The engine cooling fan speed should increase when idle
speed is doubled by pushing the accelerator pedal down.
If it does not, the vehicle needs service. Turn off the
engine.Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
Overheated Engine Protection Operating Mode on
page 5-35for information on driving to a safe place
in an emergency.
Notice:Using coolant other than DEX-COOL
®can
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant could
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by the vehicle warranty.
Always use DEX-COOL
®(silicate-free) coolant in
the vehicle.
How to Add Coolant to the Coolant
Surge Tank
If you have not found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the coolant level is not at or above the FULL COLD
mark, add a 50/50 mixture of clean, drinkable water
and DEX-COOL
®coolant at the coolant surge tank, but
be sure the cooling system, including the coolant
surge tank pressure cap, is cool before you do it. See
Engine Coolant on page 5-31for more information.
5-28

5. With the coolant surge tank pressure cap off, start
the engine and let it run until you can feel the upper
radiator hose getting hot. Watch out for the
engine cooling fan.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge tank
until the level reaches the FULL COLD mark.
6. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
7. Verify coolant level after engine is shut off and the
coolant is cold. If necessary, repeat coolant ll
procedure steps 1 through 7.
Engine Coolant
The cooling system in the vehicle is lled with
DEX-COOL®engine coolant. This coolant is designed
to remain in the vehicle for ve years or 150,000 miles
(240 000 km), whichever occurs rst, if you add only
DEX-COOL
®extended life coolant.
The following explains the cooling system and how to add
coolant when it is low. If you have a problem with engine
overheating, seeEngine Overheating on page 5-33.
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
®can
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 the vehicle warranty. Always use
DEX-COOL
®(silicate-free) coolant in the vehicle.
5-31

If you get the ENGINE COOLANT HOT message with
no sign of steam, try this for a minute or so:
1. Turn on the heater to full hot at the highest fan
speed and open the windows as necessary.
2. If you are in a traffic jam, shift to N (Neutral);
otherwise, shift to the highest gear while
driving—D(Drive).
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 and you have not stopped, 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 and get everyone out of the vehicle until it
cools down. Also, see “Overheated Engine Protection
Operating Mode” later in this section.
You may 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 the 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 5-15.
5-35

Brake Wear
This vehicle has disc brakes. Disc brake pads have
built-in wear indicators that make a high-pitched warning
sound when the brake pads are worn and new pads
are needed. The sound can come and go or be heard all
the time the vehicle is moving, except when applying
the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that soon
the brakes will not work well. That could lead to an
accident. When the brake wear warning sound is
heard, have the vehicle serviced.
Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates can cause a brake
squeal when the brakes are rst applied or lightly applied.
This does not mean something is wrong with the brakes.Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to torque specications in
Capacities and Specifications on page 5-117.
Brake linings should always be replaced as complete
axle sets.
Brake Pedal Travel
See your dealer/retailer if the brake pedal does not
return to normal height, or if there is a rapid increase in
pedal travel. This could be a sign that brake service
might be required.
Brake Adjustment
Every brake stop, the disc brakes adjust for wear.
5-40

10. Now start the vehicle with the good battery and run
the engine for awhile.
11. Try to start the vehicle that had the dead battery.
If it will not start after a few tries, it probably needs
service.
Notice:If the jumper cables are connected or
removed in the wrong order, electrical shorting may
occur and damage the vehicle. The repairs would
not be covered by the vehicle warranty. Always
connect and remove the jumper cables in the correct
order, making sure that the cables do not touch
each other or other metal.
A. Heavy, Unpainted Metal Engine Part or Remote
Negative (−) Terminal
B. Good Battery or Remote Positive (+) and
Negative (−) Terminals
C. Dead Battery or Remote Positive (+) TerminalJumper Cable Removal
5-46