fuel HUMMER H3 2010 Owner's Manual

9-36 Driving and Operating
To prevent gear damage, this
system also prevents cranking if
the engine is already running.
Engine cranking can be stopped
by turning the ignition switch to
ACC/ACCESSORY or
LOCK/OFF.
Notice: Cranking the engine for
long periods of time, by returning
the key to the START position
immediately after cranking has
ended, can overheat and damage
the cranking motor, and drain the
battery. Wait at least 15 seconds
between each try, to let the
cranking motor cool down.
2. If the engine does not start
after 5‐10 seconds, especially
in very cold weather (below 0°F
or−18°C), it could be flooded
with too much gasoline. Push
the accelerator pedal all the way
to the floor and holding it there
as you hold the key in START
for a maximum of 15 seconds. Wait at least 15 seconds
between each try, to allow the
cranking motor to cool. When
the engine starts, let go of the
key and accelerator. If the
vehicle starts briefly but then
stops again, repeat the
procedure. This clears the extra
gasoline from the engine. Do not
race the engine immediately
after starting it. Operate the
engine and transmission gently
until the oil warms up and
lubricates all moving parts.
Notice: The engine is designed to
work with the electronics in the
vehicle. If you add electrical
parts or accessories, you could
change the way the engine
operates. Before adding electrical
equipment, check with your
dealer. If you do not, the engine
might not perform properly. Any
resulting damage would not be
covered by the vehicle warranty.Engine Coolant Heater
The engine coolant heater can
provide easier starting and better
fuel economy during engine
warm-up in cold weather conditions
at or below −18°C (0°F). Vehicles
with an engine coolant heater
should be plugged in at least
four hours before starting. An
internal thermostat in the plug-end
of the cord may exist which will
prevent engine coolant heater
operation at temperatures
above −18°C (0° F).
To Use the Engine Coolant
Heater
1. Turn off the engine.
2. Open the hood and unwrap
the electrical cord. The cord
is located in the engine
compartment behind the
underhood fuse block on the
driver side of the vehicle.

Driving and Operating 9-43
To rock the vehicle back and forth to
get out of snow, ice, or sand without
damaging the transmission, see
If the Vehicle is Stuck on page 9‑26.
N (Neutral):In this position, the
engine does not connect with the
wheels. To restart the engine when
the vehicle is already moving, use
N (Neutral) only.
{WARNING
Shifting into a drive gear while the
engine is running at high speed is
dangerous. Unless your foot is
firmly on the brake pedal, the
vehicle could move very rapidly.
You could lose control and hit
people or objects. Do not shift
into a drive gear while the engine
is running at high speed. Notice:
Shifting out of P (Park)
or N (Neutral) with the engine
running at high speed may
damage the transmission. The
repairs would not be covered by
the vehicle warranty. Be sure the
engine is not running at high
speed when shifting the vehicle.
D (Drive): This position is for
normal driving. It provides the best
fuel economy. If you need more
power for passing, and you are:.Going less than about 55 km/h
(35 mph), push the accelerator
pedal about halfway down.
.Going about 55 km/h (35 mph) or
more, push the accelerator all
the way down. Downshifting the transmission in
slippery road conditions could result
in skidding, see
“Skidding”under
Loss of Control on page 9‑6.
D (Drive) can be used when towing
a trailer. You may want to shift
the transmission to 3 (Third) or,
if necessary, a lower gear if the
transmission shifts too often under
heavy loads or in hilly conditions.
3 (Third): This position is also
used for normal driving. However it
reduces vehicle speed more than
D (Drive) without using the brakes.
You might choose 3 (Third) instead
of D (Drive) when driving on hilly or
winding roads, or when towing a
trailer, so there is less shifting
between gears, or when going down
a steep hill.

Driving and Operating 9-45
You can shift into 1 (First) when
you are going less than 30 km/h
(20 mph). If you have come to a
complete stop and it is hard to shift
into 1 (First), put the shift lever in
Neutral and let up on the clutch.
Then press the clutch pedal back
down and shift into 1 (First).
2 (Second):Press the clutch pedal
as you let up on the accelerator
pedal and shift into 2 (Second).
Then, slowly let up on the clutch
pedal as you press the accelerator
pedal.
3 (Third), 4 (Fourth) and 5 (Fifth):
Shift into 3 (Third), 4 (Fourth) and
5 (Fifth) the same way you do for
2 (Second). Slowly let up on the
clutch pedal as you press the
accelerator pedal.
To stop, let up on the accelerator
pedal and press the brake pedal.
Just before the vehicle stops, press
the clutch pedal and the brake
pedal, and shift to Neutral.
Neutral: Use this position when
you start or idle the engine. R (Reverse):
To back up, stop the
vehicle. Press the clutch pedal and
shift into R (Reverse). Slowly let up
on the clutch pedal as you press
the accelerator pedal. If it is hard
to shift, let the shift lever return to
Neutral and release the clutch
pedal. Then press the clutch again
and shift into R (Reverse). Do not
attempt to shift into the fifth gear
position prior to shifting into
R (Reverse). The transmission has
a lock out feature which prevents a
5 (Fifth) gear to R (Reverse) gear
shift.
Notice: Shifting to R (Reverse)
while the vehicle is moving
forward could damage the
transmission. The repairs would
not be covered by the vehicle
warranty. Shift to R (Reverse) only
after the vehicle is stopped.
Use R (Reverse), along with the
parking brake, for parking the
vehicle.Up-Shift Light
This light will show you when to shift
to the next higher gear for best fuel
economy.
When this light comes on, you
can shift to the next higher gear if
weather, road and traffic conditions
permit. For the best fuel economy,
accelerate slowly and shift when the
light comes on.
While you accelerate, it is normal
for the light to go on and off if you
quickly change the position of the
accelerator. Ignore the shift light
when you downshift.
Disregard the shift light when the
transfer case is in four-wheel low.
For more information, see Up-Shift
Light on page 5‑15.

9-64 Driving and Operating
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.
Look for the TOP TIER label on the
fuel pump to ensure gasoline meets
enhanced detergency standards
developed by auto companies. A list
of marketers providing TOP TIER
Detergent Gasoline can be found at
www.toptiergas.com.
The 8th digit of the Vehicle
Identification Number (VIN) shows
the code letter or number that
identifies the vehicle's engine.The VIN is at the top left of the
instrument panel. See
Vehicle
Identification Number (VIN)
on
page 12‑1.
If the vehicle has the 5.3L V8 engine
(VIN Code P), you can use either
unleaded gasoline or ethanol fuel
containing up to 85% ethanol (E85).
See Fuel E85 (85% Ethanol)
on
page 9‑66. In all other engines, use
only regular unleaded gasoline.
Recommended Fuel
Use regular unleaded gasoline with
a posted octane rating of 87 or
higher. If the octane rating is less
than 87, an audible knocking noise,
commonly referred to as spark
knock, might be heard when driving.
If this occurs, use a gasoline rated
at 87 octane or higher as soon as
possible. If heavy knocking is heard
when using gasoline rated at
87 octane or higher, the engine
needs service.

Driving and Operating 9-65
Gasoline Specifications
At a minimum, gasoline should
meet ASTM specification 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. SeeFuel Additives
on page 9‑65for additional
information.
California Fuel
Requirements
If the vehicle is certified to meet
California Emissions Standards, it is
designed to operate on fuels that
meet California specifications. 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 specifications, but emission
control system performance might be affected. The malfunction
indicator lamp could turn on and the
vehicle might fail a smog‐check test.
See
Malfunction Indicator Lamp
on
page 5‑12. If this occurs, return to
your authorized 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.
Fuels in Foreign
Countries
If you plan on driving in another
country outside the United States or
Canada, the proper fuel might be
hard to find. Never use leaded
gasoline or any other fuel not
recommended in the previous text
on fuel. Costly repairs caused by
use of improper fuel would not be
covered by the vehicle warranty.
To check the fuel availability, ask an
auto club, or contact a major oil
company that does business in the
country where you will be driving.
Fuel 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, nothing
should have to be added 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. Look for the TOP TIER
label on the fuel pump to ensure
gasoline meets enhanced
detergency standards developed
by the auto companies. A list of
marketers providing TOP TIER
Detergent Gasoline can be found at
www.toptiergas.com.

9-66 Driving and Operating
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 HUMMER. It is
available at your dealer/retailer.
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
specifications 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
Identification Number (VIN) shows
the code letter or number that
identifies the vehicle's engine.
The VIN is at the top left of the
instrument panel. See Vehicle
Identification Number (VIN)
on
page 12‑1.
If the vehicle has the 5.3L V8 engine
(VIN Code P), you can use either
unleaded gasoline or ethanol fuel
containing up to 85% ethanol (E85).
In all other engines, use only the
unleaded gasoline described under
Recommended Fuel on page 9‑64.
Only vehicles that have the
5.3L V8 engine (VIN Code P)
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.

Driving and Operating 9-67
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 find 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 Specification D 5798. By
definition, 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
specifications 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 specification
D 5798. If you have trouble starting
on 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 0°C
(32°F), 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 11 L (three gallons) when
refueling. You should drive the
vehicle immediately after refueling
for at least 11 km (seven miles) 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
refill the fuel tank more often when
using E85 than when you are using
gasoline. See
Filling the Tank
on
page 9‑68.
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.

9-68 Driving and Operating
Filling the Tank
{WARNING
Fuel vapor burns violently and a
fuel fire can cause bad injuries.
To help avoid injuries to you and
others, read and follow all the
instructions on the fuel pump
island. Turn off the engine when
refueling. Do not smoke near fuel
or when refueling the vehicle. Do
not use cellular phones. Keep
sparks, flames, and smoking
materials away from fuel. Do not
leave the fuel pump unattended
when refueling the vehicle. This is
against the law in some places.
Do not re-enter the vehicle while
pumping fuel. Keep children away
from the fuel pump; never let
children pump fuel.
The fuel cap is located on the driver
side of the vehicle.
To remove the fuel cap, turn it
slowly counterclockwise. While
refueling, let the fuel cap hang by
the tether, if it has one.
When reinstalling the cap, turn
it clockwise until three clicks,
otherwise the Malfunction
Indicator Lamp could turn on.
SeeMalfunction Indicator Lamp
on
page 5‑12.
{WARNING
Fuel can spray out on you if you
open the fuel cap too quickly.
If you spill fuel and then
something ignites it, you could
be badly burned. This spray can
happen if the tank is nearly full,
and is more likely in hot weather.
Open the fuel cap slowly and wait
for any hiss noise to stop. Then
unscrew the cap all the way.
Be careful not to spill fuel. Do not
top off or overfill the tank and wait
a few seconds after you have
finished pumping before removing
the nozzle. Clean fuel from painted
surfaces as soon as possible. See
Exterior Care on page 10‑92.
When replacing the fuel cap,
turn it clockwise until three clicks.
Make sure the cap is fully installed.
The diagnostic system can
determine if the fuel cap has been
left off or improperly installed.

Driving and Operating 9-69
This would allow fuel to evaporate
into the atmosphere. See
Malfunction Indicator Lamp
on
page 5‑12.
The FUEL CAP message displays
on the Driver Information Center
(DIC) if the fuel cap is not properly
installed. See Fuel System
Messages
on page 5‑24for
more information.
{WARNING
If a fire starts while you are
refueling, do not remove the
nozzle. Shut off the flow of fuel
by shutting off the pump or by
notifying the station attendant.
Leave the area immediately.
Notice: If a new fuel cap is
needed, be sure to get the right
type of cap from your dealer.
The wrong type fuel cap might
not fit properly, might cause the
malfunction indicator lamp to light, and could damage the fuel
tank and emissions system.
See
Malfunction Indicator Lamp
on page 5‑12.
Filling a Portable Fuel
Container
{WARNING
Never fill a portable fuel container
while it is in the vehicle. Static
electricity discharge from the
container can ignite the fuel
vapor. You can be badly burned
and the vehicle damaged if this
occurs. To help avoid injury to you
and others:
.Dispense fuel only into
approved containers.
.Do not fill a container while
it is inside a vehicle, in a
vehicle's trunk, pickup bed,
or on any surface other than
the ground.
(Continued)
WARNING (Continued)
.Bring the fill nozzle in contact
with the inside of the fill
opening before operating the
nozzle. Contact should be
maintained until the filling is
complete.
.Do not smoke while
pumping fuel.
.Do not use a cellular phone
while pumping fuel.

9-70 Driving and Operating
Towing
General Towing
Information
Only use towing equipment that
has been designed for the vehicle.
Contact your dealer or trailering
retailer for assistance with preparing
the vehicle for towing a trailer.
See the following trailer towing
information in this section:
.For information on driving while
towing a trailer, see“Driving
Characteristics and
Towing Tips”.
.For maximum vehicle and trailer
weights, see “Trailer Towing”.
.For information on equipment
to tow a trailer, see “Towing
Equipment”. For information on towing a disabled
vehicle, see
Towing the Vehicle
on
page 10‑90. For information on
towing the vehicle behind another
vehicle —such as a motorhome,
see Recreational Vehicle Towing
on
page 10‑90.
Driving Characteristics
and Towing Tips
{WARNING
The driver can lose control when
pulling a trailer if the correct
equipment is not used or the
vehicle is not driven properly.
For example, if the trailer is too
heavy, the brakes may not work
well —or even at all. The driver
and passengers could be
seriously injured. The vehicle
may also be damaged; the
resulting repairs would not be
covered by the vehicle warranty.
(Continued)
WARNING (Continued)
Pull a trailer only if all the steps in
this section have been followed.
Ask your dealer for advice and
information about towing a trailer
with the vehicle.
Notice: Pulling a trailer
improperly can damage the
vehicle and result in costly
repairs not covered by the
vehicle warranty. To pull a trailer
correctly, follow the advice in this
section and see your dealer for
important information about
towing a trailer with the vehicle.
The vehicle can tow a trailer when it
is equipped with the proper trailer
towing equipment. For trailering
capacity, see Trailer Towing
on
page 9‑74. Trailering changes
handling, acceleration, braking,
durability and fuel economy.