maintenance HUMMER H2 2007 User Guide

After Off-Road Driving
Remove any brush or debris that has collected
on the underbody, chassis, or under the hood.
These accumulations can be a re hazard.
After operation in mud or sand, have the brake
linings cleaned and checked. These substances
can cause glazing and uneven braking. Check the
engine and oil coolers for mud accumulation.
Thoroughly and carefully clean these devices to
allow proper cooling. Check the body structure,
steering, suspension, wheels, tires, and exhaust
system for damage. Also, check the fuel lines and
cooling system for any leakage.
Your vehicle will require more frequent service
due to off-road use. See the Maintenance
Schedule for additional information.
Assist Steps
Your vehicle may be equipped with removable
side steps.
Remove the steps prior to off-roading to give your
vehicle more ground clearance and to prevent
damage to the vehicle from the side steps
dragging and/or catching on obstacles.
Notice:Do not drive off-road with the side
steps attached to your vehicle. You can damage
the side steps and/or your vehicle’s frame if
they get caught or drag against an obstacle.
This damage would not be covered by your
vehicle’s warranty. Always remove the side
steps prior to any off-road driving.
338

When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal
down while you:
start your engine,
shift into a gear, and
release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the
chocks.
4. Stop and have someone pick up and store
the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when
you’re pulling a trailer. See the Maintenance
Schedule for more on this. Things that are
especially important in trailer operation are
automatic transmission uid (don’t overll),
engine oil, axle lubricant, belts, cooling system
and brake system. Each of these is covered in
this manual, and the Index will help you nd them
quickly. If you’re trailering, it’s a good idea to
review these sections before you start your trip.
Check periodically to see that all hitch nuts
and bolts are tight.
385

Tires......................................................... 499
Sheet Metal Damage................................. 499
Finish Damage.......................................... 499
Underbody Maintenance............................ 500
Chemical Paint Spotting............................ 500
Vehicle Care/Appearance Materials............ 501
Vehicle Identication.................................. 502
Vehicle Identication Number (VIN)........... 502
Service Parts Identication Label............... 502Electrical System........................................ 503
Add-On Electrical Equipment..................... 503
Windshield Wiper Fuses............................ 503
Power Windows and Other Power
Options.................................................. 503
Fuses and Circuit Breakers....................... 504
Instrument Panel Fuse Block..................... 504
Center Instrument Panel Fuse Block......... 506
Underhood Fuse Block.............................. 507
Capacities and Specications.................... 512
Section 5 Service and Appearance Care
391

California Proposition 65 Warning
Most motor vehicles, including this one, contain
and/or emit chemicals known to the State of
California to cause cancer and birth defects or other
reproductive harm. Engine exhaust, many parts and
systems (including some inside the vehicle), many
uids, and some component wear by-products
contain and/or emit these chemicals.
Doing Your Own Service Work
{CAUTION:
You can be injured and your vehicle could
be damaged if you try to do service work
on a vehicle without knowing enough
about it.
Be sure you have sufficient knowledge,
experience, the proper replacement
parts, and tools before you attempt any
vehicle maintenance task.
CAUTION: (Continued)
CAUTION: (Continued)

Be sure to use the proper nuts, bolts,
and other fasteners. English and
metric fasteners can be easily
confused. If you use the wrong
fasteners, parts can later break or fall
off. You could be hurt.
If you want to do some of your own service work,
you will want to use the proper service manual.
It tells you much more about how to service your
vehicle than this manual can. To order the
proper service manual, seeService Publications
Ordering Information on page 553.
Your vehicle has an airbag system. Before
attempting to do your own service work, see
Servicing Your Airbag-Equipped Vehicle on
page 88.
You should keep a record with all parts receipts
and list the mileage and the date of any service
work you perform. SeeMaintenance Record
on page 532.
393

Adding Equipment to the Outside
of Your Vehicle
Things you might add to the outside of your
vehicle can affect the airow around it. This may
cause wind noise and affect windshield washer
performance. Check with your dealer before
adding equipment to the outside of your vehicle.
Fuel
Use of the recommended fuel is an important
part of the proper maintenance of your vehicle.
To help keep your engine clean and maintain
optimum vehicle performance, GM recommends
the use of gasoline advertised as TOP TIER
Detergent Gasoline.
Gasoline Octane
Use regular unleaded gasoline with a posted
octane rating of 87 or higher. If the octane rating
is less than 87, you may 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, your engine
needs service.
Gasoline Specications
At a minimum, gasoline should meet ASTM
specication D 4814 in the United States or
CAN/CGSB-3.5 in Canada. Some gasolines may
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl
(MMT). General Motors recommends against the
use of gasolines containing MMT. SeeAdditives
on page 395for additional information.
394

Engine Air Cleaner/Filter
Notice:If you spray water into the engine
air cleaner/lter intake and water enters
the engine air cleaner/lter housing, as shown
in the illustration, you could damage your
vehicle’s engine. The repairs would not
be covered by your warranty. Do not spray
water into the engine air cleaner/lter intake
and/or housing.SeeEngine
Compartment Overview
on page 402for the
location of the engine
air cleaner/lter and the
air lter restriction
indicator, if equipped.
When to Inspect the Engine
Air Cleaner/Filter
If your vehicle is equipped with 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,
you should inspect the air cleaner/lter at every
oil change and replace it at the rst oil change
after 100,000 miles (160 000 km). SeeScheduled
Maintenance on page 517for more information.
409

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 your 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. See
Additional Required Services on page 520.
{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 your engine, which will
damage it. Always have the air cleaner/lter in
place when you are driving.
411

3. Check both sides of the dipstick, and read the
lower level. The uid 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 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 inconsistent readings
persist, check the transmission breather hose to
be sure it is clean and unclogged. If readings
are still inconsistent, contact your dealer.
How to Add Automatic
Transmission Fluid
Refer to the Maintenance Schedule to determine
what kind of transmission uid to use. See
Recommended Fluids and Lubricants on page 528.
Add uid only after checking the transmission
uid while it is hot. A cold check is used only as
a reference. If the uid level is low, add only
enough of the proper uid to bring the level up to
the HOT area for a hot check. It does not take
much uid, generally less than one pint (0.5 L).
Do not overll.
414

Notice:Use of the incorrect automatic
transmission uid may damage your vehicle,
and the damages may not be covered by
your warranty. Always use the automatic
transmission uid listed inRecommended
Fluids and Lubricants on page 528.
After adding uid, recheck the uid level as
described under “How to Check Automatic
Transmission Fluid,” earlier in this section.
When the correct uid level is obtained, push
the dipstick back in all the way; then ip the
handle down to lock the dipstick in place.
Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is
designed to remain in your 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 your cooling system and
how to add coolant when it is low. If you have a
problem with engine overheating, seeEngine
Overheating on page 418.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
®
may 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 your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your
vehicle.
415

Brakes
Brake Fluid
Your brake master
cylinder reservoir is
lled with DOT-3 brake
uid. SeeEngine
Compartment Overview
on page 402for the
location of the reservoir.
There are only two reasons why the brake uid
level in the reservoir might go down. The rst
is that the brake uid goes down to an acceptable
level during normal brake lining wear. When new
linings are put in, the uid level goes back up.
The other reason is that uid is leaking out of the
brake system. If it is, you should have your
brake system xed, since a leak means that
sooner or later your brakes will not work well, or
will not work at all.So, it is not a good idea to top off your brake uid.
Adding brake uid will not correct a leak. If you
add uid when your linings are worn, then you will
have too much uid when you get new brake
linings. You should add or remove brake uid,
as necessary, only when work is done on
the brake hydraulic system.
{CAUTION:
If you have too much brake uid, it can
spill on the engine. The uid will burn if
the engine is hot enough. You or others
could be burned, and your vehicle could
be damaged. Add brake uid only when
work is done on the brake hydraulic
system. See “Checking Brake Fluid” in
this section.
Refer to the Maintenance Schedule to determine
when to check your brake uid. SeeScheduled
Maintenance on page 517.
427