tires HUMMER H3 2008 Owner's Manual

{CAUTION:
If you do not shift down, the brakes could get
so hot that they would not work well. You
would then have poor braking or even none
going down a hill. You could crash. Shift down
to let the engine assist the brakes on a steep
downhill slope.
{CAUTION:
Coasting downhill in NEUTRAL (N) or with the
ignition off is dangerous. The brakes will have
to do all the work of slowing down and they
could get so hot that they would not work well.
You would then have poor braking or even
none going down a hill. You could crash.
Always have the engine running and your
vehicle in gear when you go downhill.
Stay in your own lane. Do not swing wide or cut
across the center of the road. Drive at speeds
that let you stay in your own lane.
Top of hills: Be alert — something could be in your
lane (stalled car, accident).
Pay attention to special road signs (falling rocks
area, winding roads, long grades, passing or
no-passing zones) and take appropriate action.
SeeOff-Road Driving on page 4-12for information
about driving off-road.
Winter Driving
Here are some tips for winter driving:
Have your vehicle in good shape for winter.
You might want to put winter emergency supplies in
your vehicle.
Include an ice scraper, a small brush or broom,
a supply of windshield washer uid, a rag, some
winter outer clothing, a small shovel, a ashlight, a
red cloth, and a couple of reective warning triangles.
And, if you will be driving under severe conditions,
include a small bag of sand, a piece of old carpet,
or a couple of burlap bags to help provide traction.
Be sure you properly secure these items in your vehicle.
Also seeTires on page 5-54.
4-35

Driving on Snow or Ice
Most of the time, those places where the tires meet the
road probably have good traction.
However, if there is snow or ice between the tires and
the road, you can have a very slippery situation. You
have a lot less traction, or grip, and need to be very
careful.What is the worst time for this? Wet ice. Very cold snow
or ice can be slick and hard to drive on. But wet ice can
be even more trouble because it can offer the least
traction of all. You can get wet ice when it is about
freezing, 32°F (0°C), and freezing rain begins to fall.
Try to avoid driving on wet ice until salt and sand
crews can get there.
Whatever the condition — smooth ice, packed, blowing,
or loose snow — drive with caution.
The Traction Control System (TCS) improves your ability
to accelerate when driving on a slippery road. TCS
improves your ability to accelerate. SeeIf Your Vehicle
is Stuck in Sand, Mud, Ice, or Snow on page 4-39. Even
though you have TCS, slow down and adjust your driving
to the road conditions. Under certain conditions, you
might want to turn the TCS off, such as when driving
through deep snow and loose gravel, to help maintain
vehicle motion at lower speeds. SeeTraction Control
System (TCS) on page 4-5andStabiliTrak
®System on
page 4-7.
4-36

Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine again
and repeat this only when you feel really uncomfortable
from the cold. But do it as little as possible. Preserve the
fuel as long as you can. To help keep warm, you can get
out of the vehicle and do some fairly vigorous exercises
every half hour or so until help comes.
If Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow
Slowly and cautiously spin the wheels to free your
vehicle when stuck in sand, mud, ice, or snow. See
Rocking Your Vehicle to Get It Out on page 4-40.
If your vehicle has a traction system, it can often help
to free a stuck vehicle. Refer to your vehicle’s traction
system in the Index. If the stuck condition is too
severe for the traction system to free the vehicle, turn
the traction system off and use the rocking method.
{CAUTION:
If you let your vehicle’s tires spin at high
speed, they can explode, and you or others
could be injured. The vehicle can overheat,
causing an engine compartment re or other
damage. Spin the wheels as little as possible
and avoid going above 35 mph (55 km/h) as
shown on the speedometer.
For information about using tire chains on your vehicle,
seeTire Chains on page 5-77.
4-39

Tire and Loading Information Label
A vehicle specic Tire and Loading Information
label is attached to the vehicle’s center pillar
(B-pillar). With the driver’s door open, you will
nd the label attached below the door latch post.
The Tire and Loading Information label shows the
number of occupant seating positions (A), and the
maximum vehicle capacity weight (B) in kilograms
and pounds.The Tire and Loading Information label also
shows the size of your vehicle’s original equipment
tires (C) and the recommended cold tire ination
pressures (D). For more information on tires and
ination seeTires on page 5-54andInflation - Tire
Pressure on page 5-62.
There is also important information on the
Certication/Tire label. It tells you the Gross
Vehicle Weight Rating (GVWR) and the Gross
Axle Weight Rating (GAWR) for the front and rear
axles. See “Certication/Tire Label” later in this
section.
Steps for Determining Correct Load Limit
1.Locate the statement “The combined weight of
occupants and cargo should never exceed
XXX kg or XXX lbs” on your vehicle’s placard.
2.Determine the combined weight of the driver
and passengers that will be riding in your
vehicle.
3.Subtract the combined weight of the driver
and passengers from XXX kg or XXX lbs.
Label Example
4-43

If You Do Decide To Pull A Trailer
If you do, here are some important points:
There are many different laws, including speed
limit restrictions, having to do with trailering. Make
sure your rig will be legal, not only where you live
but also where you’ll be driving. A good source for
this information can be state or provincial police.
Consider using a sway control. See “Hitches” later in
this section.
Don’t tow a trailer at all during the rst 500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
Then, during the rst 500 miles (800 km) that you tow
a trailer, don’t drive over 50 mph (80 km/h) and don’t
make starts at full throttle. This helps your engine
and other parts of your vehicle wear in at the
heavier loads.
If you have an automatic transmission, you can tow
in DRIVE (D). You may want to shift the transmission
to THIRD (3) or, if necessary, a lower gear if the
transmission shifts too often under heavy loads
and/or hilly conditions. If you have a manual
transmission and you are towing a trailer, it is
better not to use the highest gear.
Three important considerations have to do with weight:
The weight of the trailer
The weight of the trailer tongue
And the weight on your vehicle’s tires
4-51

After you’ve loaded your trailer, weigh the trailer and
then the tongue, separately, to see if the weights
are proper. If they aren’t, you may be able to get
them right simply by moving some items around
in the trailer.
Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inated to the upper
limit for cold tires. You’ll nd these numbers on the
Certication/Tire Label located on the B-pillar below the
door latch or seeLoading Your Vehicle on page 4-42.
Then be sure you don’t go over the GVW limit for your
vehicle, or the GAWR, including the weight of the trailer
tongue. If you use a weight distributing hitch, make sure
you don’t go over the rear axle limit before you apply the
weight distribution spring bars.
Hitches
It’s important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads
are a few reasons why you’ll need the right hitch.
Weight-Distributing Hitches and Weight
Carrying Hitches
When using a weight-distributing hitch, the hitch must be
adjusted so that the distance (A) remains the same both
before and after coupling the trailer to the tow vehicle.
Trailering may also be limited by the vehicle’s ability
to carry tongue weight. Tongue weight cannot cause
the vehicle to exceed the GVWR (Gross Vehicle Weight
Rating) or the RGAWR (Rear Gross Axle Weight
Rating). The effect of additional weight may reduce
your trailering capacity more than the total of the
additional weight.(A) Body-to-Ground Distance (B) Front of Vehicle
4-54

The effect of tongue weight is about 1.5 times the actual
weight. Dividing the 900 lbs (408 kg) by 1.5 leaves you
with being able to handle only 600 lbs (272 kg) of tongue
weight. Since tongue weight is usually at least 10 percent
of total loaded trailer weight, you can expect that the
largest trailer your vehicle can properly handle is
6,000 lbs (2 721 kg).
It is important that you make sure your vehicle does not
exceed any of its ratings — GCWR, GVWR, RGAWR,
Maximum Trailer Rating or Tongue Weight. The
only way to be sure you are not exceeding any
of these ratings is to weigh your vehicle and trailer.
Safety Chains
You should always attach chains between your vehicle
and your trailer. Cross the safety chains under the tongue
of the trailer to help prevent the tongue from contacting
the road if it becomes separated from the hitch. Always
leave just enough slack so you can turn with your rig.
Never allow safety chains to drag on the ground.
Trailer Brakes
If your trailer weighs more than 1,500 lbs (680 kg)
loaded, then it needs its own brakes – and they must be
adequate. Be sure to read and follow the instructions
for the trailer brakes so you’ll be able to install,
adjust and maintain them properly.
Driving with a Trailer
Towing a trailer requires a certain amount of experience.
Before setting out for the open road, you’ll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the
trailer. And always keep in mind that the vehicle you
are driving is now a good deal longer and not nearly
as responsive as your vehicle is by itself.
Before you start, check all trailer hitch parts and
attachments, safety chains, electrical connector, lamps,
tires and mirror adjustment. If the trailer has electric
brakes, start your vehicle and trailer moving and then
apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer
brakes are still working.
4-56

Tires..............................................................5-54
Tire Sidewall Labeling...................................5-55
Tire Terminology and Denitions.....................5-59
Ination - Tire Pressure.................................5-62
Tire Pressure Monitor System.........................5-63
Tire Pressure Monitor Operation.....................5-65
Tire Inspection and Rotation...........................5-68
When It Is Time for New Tires.......................5-70
Buying New Tires.........................................5-71
Different Size Tires and Wheels......................5-73
Uniform Tire Quality Grading..........................5-74
Wheel Alignment and Tire Balance..................5-75
Wheel Replacement......................................5-75
Tire Chains..................................................5-77
If a Tire Goes Flat........................................5-78
Changing a Flat Tire.....................................5-79
Removing the Spare Tire and Tools................5-81
Removing the Flat Tire and Installing the
Spare Tire................................................5-83
Storing a Flat or Spare Tire and Tools............5-89
Spare Tire...................................................5-91
Appearance Care............................................5-91
Interior Cleaning...........................................5-91
Fabric/Carpet...............................................5-93
Leather.......................................................5-93
Instrument Panel, Vinyl, and Other Plastic
Surfaces..................................................5-94Care of Safety Belts......................................5-94
Weatherstrips...............................................5-94
Washing Your Vehicle...................................5-95
Cleaning Exterior Lamps/Lenses.....................5-95
Finish Care..................................................5-96
Windshield, Backglass, and Wiper Blades.........5-97
Aluminum or Chrome-Plated Wheels and Trim . . .5-97
Tires...........................................................5-98
Sheet Metal Damage.....................................5-98
Finish Damage.............................................5-98
Underbody Maintenance................................5-98
Chemical Paint Spotting.................................5-99
Vehicle Care/Appearance Materials..................5-99
Vehicle Identication.....................................5-100
Vehicle Identication Number (VIN)................5-100
Service Parts Identication Label...................5-101
Electrical System..........................................5-101
Add-On Electrical Equipment.........................5-101
Windshield Wiper Fuses...............................5-101
Power Windows and Other Power Options......5-102
Fuses and Circuit Breakers..........................5-102
Engine Compartment Fuse Block...................5-103
Capacities and Specications........................5-107
Capacities and Specications........................5-107
Section 5 Service and Appearance Care
5-2

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

Four-Wheel Drive
It is recommended that the four-wheel drive transfer
case uid be checked and lled by your dealer.
Front Axle
It is not necessary to regularly check front axle uid
unless you suspect there is a leak or you hear an
unusual noise. A uid loss could indicate a problem.
It is recommended that the front axle uid be checked
and lled by your dealer.
Headlamp Aiming
The vehicle may have a visual optical headlamp aiming
system. The aim has been preset at the factory and
should need no further adjustment.
However, if the vehicle is damaged in a crash, the
headlamp aim may be affected and adjustment may be
necessary.
If oncoming vehicles ash their high beams at you, this
may also mean the vertical aim needs to be adjusted.It is recommended that the vehicle is taken to your
dealer/retailer for service if the headlamps need to be
re-aimed. It is possible however, to re-aim the
headlamps as described.
The vehicle should:
Be placed so the headlamps are 25 ft. (7.6 m) from
a light colored wall or other at surface.
Have all four tires on a level surface which is level
all the way to a wall.
Be placed so it is perpendicular to the wall or other
at surface.
Not have any snow, ice, or mud on it.
Be fully assembled and all other work stopped while
headlamp aiming is being performed.
Be normally loaded with a full tank of fuel and one
person or 160 lbs (75 kg) sitting on the driver seat.
Have the tires properly inated.
Have the spare tire is in its original location in the
vehicle.
5-46