brakes HUMMER H3 2008 Owner's Guide

Brakes
Brake Fluid
The brake master cylinder
reservoir is lled with
DOT-3 brake uid. See
Engine Compartment
Overview on page 5-12for
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 hydraulic system.
If it is, you should have the brake hydraulic system
xed, since a leak means that sooner or later the
brakes will not work well.It is not a good idea to top off the brake uid. Adding
brake uid will not correct a leak. If uid is added when
the linings are worn, there will be too much uid
when new brake linings are installed. 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 6-4.
5-38

Checking Brake Fluid
The brake uid can be checked without taking off the
cap by looking at the brake uid reservoir.
The uid level should be above MIN. If it is not, have
the brake hydraulic system checked to see if there is
a leak.
After work is done on the brake hydraulic system,
make sure the level is above the MIN but not over the
MAX mark.
What to Add
When you do need brake uid, use only DOT-3 brake
uid. Use new brake uid from a sealed container
only. SeeRecommended Fluids and Lubricants on
page 6-12.
Always clean the brake uid reservoir cap and the area
around the cap before removing it. This helps keep
dirt from entering the reservoir.
{CAUTION:
With the wrong kind of uid in the brake
hydraulic system, the brakes might not work
well. This could cause a crash. Always use the
proper brake uid.
Notice:
Using the wrong uid can badly damage brake
hydraulic system parts. For example, just a
few drops of mineral-based oil, such as engine
oil, in the brake hydraulic system can damage
brake hydraulic system parts so badly that they
will have to be replaced. Do not let someone
put in the wrong kind of uid.
If you spill brake uid on your vehicle’s painted
surfaces, the paint nish can be damaged. Be
careful not to spill brake uid on your vehicle. If
you do, wash it off immediately. SeeWashing
Your Vehicle on page 5-95.
5-39

Brake Wear
Your 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 your vehicle is moving, except when you are
pushing on 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 you hear the brake
wear warning sound, have your 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 5-107.
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 time you make a brake stop, the disc brakes
adjust for wear.
5-40

Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. Your vehicle
was designed and tested with top-quality brake parts.
When you replace parts of the braking system — for
example, when the brake linings wear down and you
need new ones put in — be sure you get new approved
replacement parts. If you do not, the brakes might not
work properly. For example, if someone puts in brake
linings that are wrong for your vehicle, the balance
between the front and rear brakes can change — for the
worse. The braking performance you have come to
expect can change in many other ways if someone puts
in the wrong replacement brake parts.
Battery
Your vehicle has a maintenance free battery. When it is
time for a new battery, see your dealer/retailer for
one that has the replacement number shown on the
original battery’s label. SeeEngine Compartment
Overview on page 5-12for battery location.
Warning:Battery posts, terminals, and related
accessories contain lead and lead compounds,
chemicals known to the State of California to cause
cancer and reproductive harm. Wash hands after
handling.
Vehicle Storage
{CAUTION:
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you
are not careful. SeeJump Starting on
page 5-42for tips on working around a battery
without getting hurt.
Infrequent Usage: If you drive your vehicle infrequently,
remove the black, negative (−) cable from the battery.
This will help keep the battery from running down.
Extended Storage: For extended storage of your vehicle,
remove the black, negative (−) cable from the battery
or use a battery trickle charger. This will help maintain
the charge of the battery over an extended period
of time.
5-41

(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire.
The letter R means radial ply construction;
the letter D means diagonal or bias ply
construction; and the letter B means belted-bias
ply construction.
(E) Rim Diameter
:Diameter of the wheel in
inches.
(F) Service Description
:The service description
indicates the load range and speed rating of a
tire. The load index can range from 1 to 279.
Speed ratings range from A to Z.
Tire Terminology and Denitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of the
tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
Aspect Ratio
:The relationship of a tire’s height
to its width.Belt
:A rubber coated layer of cords that is
located between the plies and the tread. Cords
may be made from steel or other reinforcing
materials.
Bead
:The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.
Cold Tire Pressure
:The amount of air pressure in
a tire, measured in pounds per square inch (psi) or
kilopascals (kPa) before a tire has built up heat
from driving. SeeInflation - Tire Pressure on
page 5-62.
Curb Weight
:The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant,
but without passengers and cargo.
DOT Markings
:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identication Number (TIN),
an alphanumeric designator which can also identify
the tire manufacturer, production plant, brand,
and date of production.
5-59

Your vehicle’s original equipment tires are listed
on the Tire and Loading Information Label.
SeeLoading Your Vehicle on page 4-42, for more
information about the Tire and Loading Information
Label and its location on your vehicle.
Different Size Tires and Wheels
If you add wheels or tires that are a different size than
your original equipment wheels and tires, this could
affect the way your vehicle performs, including its
braking, ride and handling characteristics, stability, and
resistance to rollover. Additionally, if your vehicle
has electronic systems such as anti-lock brakes, rollover
airbags, traction control, and electronic stability control,
the performance of these systems can be affected.
{CAUTION:
If you add different sized wheels, your vehicle
may not provide an acceptable level of
performance and safety if tires not
recommended for those wheels are selected.
You may increase the chance that you will
crash and suffer serious injury. Only use
GM specic wheel and tire systems developed
for your vehicle, and have them properly
installed by a GM certied technician.
SeeBuying New Tires on page 5-71andAccessories
and Modifications on page 5-3for additional information.
5-73

Tire Chains
{CAUTION:
If your vehicle has LT285/75R16 or P265/65R18
size tires, do not use tire chains. They can
damage your vehicle because there is not
enough clearance. Tire chains used on a
vehicle without the proper amount of clearance
can cause damage to the brakes, suspension,
or other vehicle parts. The area damaged by
the tire chains could cause you to lose control
of your vehicle and you or others may be
injured in a crash.
Use another type of traction device only if its
manufacturer recommends it for use on your
vehicle and tire size combination and road
conditions. Follow that manufacturer’s
CAUTION: (Continued)
CAUTION: (Continued)
instructions. To help avoid damage to your
vehicle, drive slowly, readjust, or remove the
device if it is contacting your vehicle, and do
not spin your vehicle’s wheels.
If you do nd traction devices that will t,
install them on the rear tires.
Notice:If your vehicle has a tire size other than
LT285/75R16 or P265/65R18 use tire chains only
where legal and only when you must. Use chains that
are the proper size for your tires. Install them on the
tires of the rear axle. Do not use chains on the tires of
the front axle. Tighten them as tightly as possible
with the ends securely fastened. Drive slowly and
follow the chain manufacturer’s instructions. If you
can hear the chains contacting your vehicle, stop and
retighten them. If the contact continues, slow down
until it stops. Driving too fast or spinning the wheels
with chains on will damage your vehicle.
5-77

Fuse Usage
7 Regulated Voltage Control Power
8 Power Locks
9 Sunroof, Front Washer Pump
10 Accessories (SPO)
11 Air Compressor
12 Transfer Case Control Module
13Radio, Heating, Ventilation, Air
Conditioning Display
14 Body Control Module
15 Rear Wiper Motor
16 Rear Wiper Pump Switch
17 Air Injection Reactor (AIR) Solenoid
18 Spare 6
19 Cluster
20 Rear Turn Signal, Hazard Signal
21 Powertrain Control Module 1
22Mass Air Flow Sensor, Purge
Solenoid
23 Injector
24 Fog Lamp
25 Powertrain Control Module B
26 Transmission Control Module (TCM)
27 Airbags
28 Back-up LampsFuse Usage
29 Antilock Brakes, StabiliTrak®
30 Rear Window Defogger
31 Canister Vent
32 Regulated Voltage Control VSense+
33 Ignition 1
34 Transmission
35 Cruise, Inside Rearview Mirror
36 Horn
37 Driver Side Rear Park Lamp
38 Amplier
39Reduced Intensity Low-Beam
Daytime Running Lamps
40 Passenger Side Headlamp
41 Driver Side Headlamp
42 Trailer Back-Up Lamp
43 Front Park Lamps
44 Air Injection Reactor (AIR) Solenoid
45 Auxiliary Power 2
46 Electronic Throttle Control
47 Oxygen Sensor
48 Air Conditioning Clutch
49 Passenger Side Rear Park Lamp
50 Spare
51 Auxiliary Power 1
5-105

Fuse Usage
52 StabiliTrak®, Antilock Brakes
53 Power Heater Switch
54 Stop
55 Trailer Parking Lamps
56 Front Turn Signal, Hazard Signal
57 Power Sunroof
58Transfer Case Control Module
Switch
59 Climate Control
60 Spare 8
61 Power Seats
62 Air Pump
63 Passenger Side Power Window
64Antilock Brakes, StabiliTrak
®2
Solenoid
67Antilock Brakes, StabiliTrak
®1
Motor
68 Driver Side Power Window
82 Climate Control Fan
83 Electronic Brake Controller
84 Trailer B+ Fuse
85 Starter
91 Megafuse
Relay Usage
66 Fuel Pump
69 Fog Lamp
70 High, Low Beam Headlamps
71 Rear Defogger
72 Windshield Wiper On/Off
73 Windshield Wiper High/Low
74 Horn
75 Headlamp
76 Air Conditioning Clutch
77 Powertrain Control Module
78 Run, Crank
79Reduced Intensity Low-Beam
Daytime Running Lamps
80 Air Injection Reactor (AIR) Solenoid
81 Powertrain (Starter)
86 Spare 2
87 Heating, Ventilation, Air Conditioning
88 Retained Accessory Power
89 Park Lamp
Diode Usage
65 Wiper Diode
90 Air Conditioning Clutch Diode
5-106

Reporting Safety Defects to the
Canadian Government
If you live in Canada, and you believe that your
vehicle has a safety defect, notify Transport Canada
immediately, in addition to notifying General Motors of
Canada Limited. Call them at 1-800-333-0510 or write to:
Transport Canada
Road Safety Branch
2780 Sheffield Road
Ottawa, Ontario K1B 3V9
Reporting Safety Defects to
General Motors
In addition to notifying NHTSA (or Transport Canada) in
a situation like this, please notify General Motors.
Call 1-866-HUMMER6 (486-6376), or write:
HUMMER Customer Assistance Center
P.O. Box 33177
Detroit, MI 48232-5177
In Canada, call 1-800-263-3777 (English) or
1-800-263-7854 (French), or write:
General Motors of Canada Limited
Customer Communication Centre CA1-163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
Service Publications Ordering
Information
Service Manuals
Service Manuals have the diagnosis and repair
information on engines, transmission, axle suspension,
brakes, electrical, steering, body, etc.
Service Bulletins
Service Bulletins’ give additional technical service
information needed to knowledgeably service
General Motors cars and trucks. Each bulletin contains
instructions to assist in the diagnosis and service of
your vehicle.
Owner Information
Owner publications are written specically for owners
and intended to provide basic operational information
about the vehicle. The owner manual includes the
Maintenance Schedule for all models.
In-Portfolio: Includes a Portfolio, Owner Manual, and
Warranty Booklet.
RETAIL SELL PRICE: $35.00 (U.S.) plus processing fee
Without Portfolio: Owner Manual only.
RETAIL SELL PRICE: $25.00 (U.S.) plus processing fee
7-15