lock HUMMER H3 2010 Owners Manual

9-56 Driving and Operating
To lock the front and rear axles:
1. Place the transfer case in the4LO Lock mode. This is the
only mode which allows the
front and rear axles to lock.
See Four-Wheel Drive
on
page 9‑46for more information
regarding the transfer case and
4LO Lock mode.
2. Press the rear axle locking button with the vehicle moving
less than 16 mph (26 km/h).
3. Wait for the light in the button to stop flashing and remain
illuminated to show that the rear
axle is locked.
4. Press the front axle locking button with the vehicle stopped
or moving less than 26 km/h
(16 mph). 5. Wait for the light in the button
to stop flashing and remain
illuminated to show that the front
axle is locked.
Notice: If you try to lock the axle
while the vehicle is stuck and the
tires are spinning, the vehicle's
drivetrain could be damaged.
The repairs would not be covered
by the vehicle warranty. Always
lock the axle before attempting
situations and/or navigating
terrain which could possibly
cause the vehicle to become
stuck. Locking axles will be disengaged
when the wheel speed is greater
than 64 km/h (40 mph), if the
vehicle's battery is low and/or the
transfer case is shifted out of
4LO Lock mode.
Notice:
If the vehicle's axle
is locked while driving on
pavement, the drivetrain could be
damaged. Repairs would not be
covered by the vehicle warranty.
Do not use the locking axle on
pavement. If four-wheel drive is
needed when traveling on
pavement, use only 4HI.

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.

9-80 Driving and Operating
The trailer towing harness contains
the following seven trailer circuits:
.Yellow: Left Stop/Turn Signal
.Dark Green: Right Stop/Turn
Signal
.Brown: Taillamps
.White: Ground
.Light Green: Back-up Lamps
.Red: Battery Feed
.Dark Blue: Trailer Brake
If charging a remote (non‐vehicle)
battery, turn on the headlamps to
boost the vehicle system voltage to
properly charge the battery. Four-Wire Harness Adapter
If towing a light-duty trailer with
a standard four-way, flat pin
connector, an adapter is available
from your dealer.
Hold the adapter with the tab
pointing up.
Connect the adapter to the
seven‐pin universal heavy‐duty
trailer connector attached to the
bracket on the hitch platform. The
flip cap on the vehicle's harness
locks onto the tab and helps hold
the adapter in place. Plug the
four-way pin connector onto the
adapter.

Vehicle Care 10-1
Vehicle Care
General Information
General Information . . . . . . . . . . 10-2
California Proposition65 Warning . . . . . . . . . . . . . . . . . 10-2
California Perchlorate Materials Requirements . . . . 10-3
Accessories and Modifications . . . . . . . . . . . . . . . 10-3
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 10-4
Hood . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . 10-6
Engine Oil . . . . . . . . . . . . . . . . . . . 10-9
Engine Oil Life System . . . . . 10-11
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . 10-12
Manual Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . 10-15 Hydraulic Clutch . . . . . . . . . . . . 10-16
Engine Air Cleaner/Filter . . . . 10-17
Cooling System . . . . . . . . . . . . 10-18
Engine Coolant . . . . . . . . . . . . . 10-19
Engine Overheating . . . . . . . . 10-22
Engine Fan . . . . . . . . . . . . . . . . . 10-24
Power Steering Fluid . . . . . . . 10-24
Washer Fluid . . . . . . . . . . . . . . . 10-25
Brakes . . . . . . . . . . . . . . . . . . . . . 10-26
Brake Fluid . . . . . . . . . . . . . . . . . 10-27
Battery . . . . . . . . . . . . . . . . . . . . . 10-28
Four-Wheel Drive . . . . . . . . . . . 10-29
Front Axle . . . . . . . . . . . . . . . . . . 10-29
Rear Axle . . . . . . . . . . . . . . . . . . 10-29
Starter Switch Check . . . . . . . 10-30
Automatic Transmission Shift
Lock Control System
Check . . . . . . . . . . . . . . . . . . . . . 10-30
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . 10-31
Park Brake and P (Park) Mechanism Check . . . . . . . . 10-31
Wiper Blade Replacement . . . . . . . . . . . . . . 10-32
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . 10-33
Bulb Replacement
Bulb Replacement . . . . . . . . . . 10-35
Halogen Bulbs . . . . . . . . . . . . . . 10-35
Headlamps . . . . . . . . . . . . . . . . . 10-35
Taillamps, Turn Signal,Stoplamps, and Back-Up
Lamps (H3) . . . . . . . . . . . . . . . 10-35
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps (H3T) . . . . . . . . . . . . . . 10-36
License Plate Lamp . . . . . . . . 10-37
Replacement Bulbs . . . . . . . . . 10-37
Electrical System
Electrical System Overload . . . . . . . . . . . . . . . . . . 10-38
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . 10-39
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-39

Vehicle Care 10-3
California Perchlorate
Materials Requirements
Certain types of automotive
applications, such as airbag
initiators, seat belt pretensioners,
and lithium batteries contained in
remote keyless transmitters, may
contain perchlorate materials.
Special handling may be necessary.
For additional information, see
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
Accessories and
Modifications
Adding non‐dealer/non‐retailer
accessories to the vehicle can affect
vehicle performance and safety,
including such things as airbags,
braking, stability, ride and handling,
emissions systems, aerodynamics,
durability, and electronic systems
like antilock brakes, traction control,
and stability control. Some of these
accessories could even cause
malfunction or damage not covered
by the vehicle warranty.
Damage to vehicle components
resulting from the installation or
use of non‐certified parts, including
control module modifications, isnot covered under the terms of the
vehicle warranty and may affect
remaining warranty coverage for
affected parts.
HUMMER Accessories are
designed to complement and
function with other systems on
the vehicle. Your HUMMER
dealer/retailer can accessorize the
vehicle using genuine HUMMER
Accessories. When you go to your
HUMMER dealer/retailer and ask
for HUMMER Accessories, you will
know that HUMMER-trained and
supported service technicians will
perform the work using genuine
HUMMER Accessories.
Also, see
Adding Equipment to the
Airbag-Equipped Vehicle
on
page 3‑40.

Vehicle Care 10-7
A. Windshield Washer FluidReservoir. See “Adding Washer
Fluid” under Washer Fluid
on
page 10‑25.
B. Engine Coolant Recovery Tank. See Engine Coolant
on
page 10‑19.
C. Engine Air Cleaner/Filter
on
page 10‑17.
D. Power Steering Fluid Reservoir. See Power Steering Fluid
on
page 10‑24.
E. Automatic Transmission Fluid Dipstick (If Equipped). See
“Checking the Fluid Level” under
Automatic Transmission Fluid
on
page 10‑12.
F. Engine Oil Fill Cap. See “When
to Add Engine Oil” underEngine
Oil on page 10‑9. G. Radiator Pressure Cap. See
Cooling System on page 10‑18.
H. Remote Negative (−) Terminal (GND). See Jump Starting
on
page 10‑86.
I. Engine Oil Dipstick. See “Checking Engine Oil” under
Engine Oil on page 10‑9.
J. Positive (+) Battery Terminal. See Jump Starting
on
page 10‑86.
K. Brake Fluid Reservoir. See “Brake Fluid” under
Brakes on page 10‑26.
L. Engine Compartment Fuse
Block on page 10‑39.
M. Battery on page 10‑28.
N. Hydraulic Clutch Fluid Reservoir (If Equipped). See Hydraulic
Clutch on page 10‑16.

Vehicle Care 10-9
A.Engine Air Cleaner/Filteron
page 10‑17.
B. Air Filter Restriction Indicator (If Equipped). See Engine Air
Cleaner/Filter
on page 10‑17.
C. Windshield Washer Fluid Reservoir. See “Adding Washer
Fluid” under Washer Fluid
on
page 10‑25.
D. Engine Coolant Recovery Tank. See Engine Coolant
on
page 10‑19.
E. Automatic Transmission Fluid Dipstick (If Equipped). See
“Checking the Fluid Level” under
Automatic Transmission Fluid
on
page 10‑12. F. Engine Oil Dipstick. See
“Checking Engine Oil” under
Engine Oil on page 10‑9.
G. Engine Oil Fill Cap. See “When
to Add Engine Oil” underEngine
Oil on page 10‑9.
H. Brake Fluid Reservoir. See “Brake Fluid” underBrakes
on
page 10‑26.
I. Battery on page 10‑28.
J. Power Steering Fluid Reservoir. See Power Steering Fluid
on
page 10‑24.
K. Engine Compartment Fuse
Block on page 10‑39.
L. Radiator Pressure Cap. See Cooling System on page 10‑18.
Engine Oil
Checking Engine Oil
It is a good idea to check the engine
oil level at each fuel fill. In order to
get an accurate reading, the oil
must be warm and the vehicle must
be on level ground.
The engine oil dipstick handle
is a yellow loop. See Engine
Compartment Overview
on
page 10‑6for the location of the
engine oil dipstick.
1. Turn off the engine and give the oil several minutes to drain back
into the oil pan. If this is not
done, the oil dipstick might not
show the actual level.
2. Pull out the dipstick and clean it with a paper towel or cloth,
then push it back in all the way.
Remove it again, keeping the tip
down, and check the level.

10-12 Vehicle Care
After changing the engine oil, reset
the system:
1. Turn the ignition key to ON/RUNwith the engine off.
2. Press and release the stem in the lower center of the
instrument cluster until the OIL
LIFE message is displayed.
3. Once the alternating “Oil Life”
and “Reset” messages appear,
press and hold the stem until
several beeps sound. This
confirms that the oil life system
has been reset.
4. Turn the key to LOCK/OFF.
If the “Change Oil” message
comes on again and stays on for
30 seconds at the next ignition
cycle, it did not reset. The system
needs to be reset again.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.
Automatic Transmission
Fluid
When to Check and Change
Automatic Transmission Fluid
A good time to check the automatic
transmission fluid level is when the
engine oil is changed.
Change the fluid and filter at the
intervals listed in Scheduled
Maintenance
on page 11‑2, and be
sure to use the transmission fluid
listed in Recommended Fluids and
Lubricants on page 11‑8.
How to Check Automatic
Transmission Fluid
Because this operation can be a
little difficult, you may choose to
have this done at the dealer service
department.
If adding it yourself, be sure to
follow all the instructions here,
or there could be a false reading on
the dipstick.

10-14 Vehicle Care
Then, without shutting off the
engine:
1. Flip the handle up and then pullout the dipstick and wipe it with
a clean rag or paper towel.
The automatic transmission
dipstick handle with this symbol
on it is located in the engine
compartment on the passenger
side of the vehicle.
See Engine Compartment
Overview
on page 10‑6for
more information on location.
2. Push it back in all the way, wait three seconds, and pull it back
out again.
3. Check both sides of the dipstick,
and read the lower level. The
fluid level must be in the COLD
area, below the cross-hatched
area, for a cold check or in the
HOT or cross-hatched area for a
hot check. Be sure to keep the
dipstick pointed down to get an
accurate reading.
4. If the fluid level is in the acceptable range, push the
dipstick back in all the way; then
flip the handle down to lock the
dipstick in place.
How to Add Automatic
Transmission Fluid
Refer to the Maintenance
Schedule to determine what kind
of transmission fluid to use. See
Recommended Fluids and
Lubricants on page 11‑8.
Add fluid 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.

Vehicle Care 10-15
Notice:Use of the incorrect
automatic transmission fluid
may damage the vehicle, and the
damages may not be covered by
the vehicle's warranty. Always
use the automatic transmission
fluid listed in Recommended
Fluids and Lubricants
on
page 11‑8.
.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.
Manual Transmission
Fluid
When to Check
A good time to check the manual
transmission fluid is when the
engine oil is changed. However, the
fluid in the manual transmission
does not require changing.
How to Check
Because this operation can be a
little difficult, you may choose to
have this done at your HUMMER
dealer service department.
If doing it yourself, be sure to follow
all the instructions here, or there
could be a false reading.
Notice: Too much or too
little fluid can damage the
transmission. Too little fluid
could cause the transmission
to overheat. Be sure to get an
accurate reading if checking the
transmission fluid. To check the fluid:
1. Park the vehicle on a level
surface, then shut the engine
off. Let the vehicle sit until the
transmission case is cool
enough to touch.
2. Remove the filler plug.
3. Check that the lubricant level isup to the bottom of the filler
plug hole.