2008 HUMMER H2 Owners Manual

Treadwear
The treadwear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specied
government test course. For example, a tire
graded 150 would wear one and a half (1.5) times
as well on the government course as a tire
graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart signicantly from
the norm due to variations in driving habits, service
practices, and differences in road characteristics
and climate.
Traction – AA, A, B, C
The traction grades, from highest to lowest, are
AA, A, B, and C. Those grades represent the
tire’s ability to stop on wet pavement as
measured under controlled conditions on specied
government test surfaces of asphalt and concrete.
A tire marked C may have poor traction
performance.
Warning
:The traction grade assigned to this
tire is based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
Temperature – A, B, C
The temperature grades are A (the highest), B,
and C, representing the tire’s resistance to
the generation of heat and its ability to dissipate
heat when tested under controlled conditions on a
specied indoor laboratory test wheel. Sustained
high temperature can cause the material of the tire
to degenerate and reduce tire life, and excessive
temperature can lead to sudden tire failure.
The grade C corresponds to a level of performance
which all passenger car tires must meet under
the Federal Motor Vehicle Safety Standard
No. 109. Grades B and A represent higher levels
of performance on the laboratory test wheel
than the minimum required by law.
Warning
:The temperature grade for this tire
is established for a tire that is properly inated
and not overloaded. Excessive speed,
underination, or excessive loading, either
separately or in combination, can cause heat
buildup and possible tire failure.
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Wheel Alignment and Tire Balance
The tires and wheels on your vehicle were aligned
and balanced carefully at the factory to give you the
longest tire life and best overall performance.
Adjustments to wheel alignment and tire balancing will
not be necessary on a regular basis. However, if
you notice unusual tire wear or your vehicle pulling to
one side or the other, the alignment might need to
be checked. If you notice your vehicle vibrating when
driving on a smooth road, the tires and wheels
might need to be rebalanced. See your dealer/retailer
for proper diagnosis.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted
or corroded. If wheel nuts keep coming loose, the
wheel, wheel bolts, and wheel nuts should be replaced.
If the wheel leaks air, replace it (except some
aluminum wheels, which can sometimes be repaired).
See your dealer/retailer if any of these conditions exist.
Your dealer/retailer will know the kind of wheel you need.Each new wheel should have the same load-carrying
capacity, diameter, width, offset, and be mounted
the same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts,
wheel nuts, or Tire Pressure Monitor System (TPMS)
sensors, replace them only with new GM original
equipment parts. This way, you will be sure to have the
right wheel, wheel bolts, wheel nuts, and TPMS
sensors for your vehicle.
{CAUTION:
Using the wrong replacement wheels, wheel
bolts, or wheel nuts on your vehicle can be
dangerous. It could affect the braking and
handling of your vehicle, make your tires lose
air and make you lose control. You could have
a collision in which you or others could be
injured. Always use the correct wheel, wheel
bolts, and wheel nuts for replacement.
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Notice:The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance, and tire or tire chain
clearance to the body and chassis.
SeeChanging a Flat Tire on page 5-78for more
information.
Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You cannot know how it has been
used or how far it has been driven. It could fail
suddenly and cause a crash. If you have to
replace a wheel, use a new GM original
equipment wheel.
Tire Chains
Notice:Use tire chains only where legal and only
when you must. Use only SAE Class U-type
chains that are the proper size for your tires. Install
them on the rear axle tires and 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.
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Accessory Inator
Your vehicle may have an accessory inator system.
You can inate things like basketballs and bicycle tires.
You can also use it to bring your tire pressure up to
the proper pressure. The engine must be running and
the gearshift lever must be in PARK (P) for the inator
to operate.
The accessory inator is
located in the rear
compartment on the
passenger’s side of
the vehicle.The accessory inator kit
includes a hose and three
nozzle adapters.
To use the accessory inator, do the following:
1. Attach the appropriate nozzle adapter to the end of
the hose.
2. Attach that end of the hose to the object you wish
to inate.
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3. Remove the dust cover and attach the hose to
the outlet.
The accessory inator hose also has a built-in air
pressure gage. As soon as you start to inate
an object it will automatically read the current
pressure.
4. Press and release the switch to turn the accessory
inator on. The indicator light will remain on while
the inator is running.When you are nished using the inator, press and
release the switch to turn it off. Place the inator kit tools
and the hose back in the pouch.
If your vehicle is equipped with the air suspension
system, load leveling will not function with the inator
hose attached to the inator outlet.
{CAUTION:
Inating something too much can make it
explode, and you or others could be injured.
Be sure to read the inator instructions, and
inate any object only to its recommended
pressure.
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If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your vehicle’s tires properly.
If air goes out of a tire, it is much more likely to leak out
slowly. But if you should ever have a blowout, here
are a few tips about what to expect and what to do:
If a front tire fails, the at tire creates a drag that pulls
the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel rmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you would
use in a skid. In any rear blowout remove your foot from
the accelerator pedal. Get the vehicle under control
by steering the way you want the vehicle to go. It may
be very bumpy and noisy, but you can still steer.
Gently brake to a stop, well off the road if possible.{CAUTION:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without
the appropriate safety equipment and training.
The jack provided with your vehicle is
designed only for changing a at tire. If it is
used for anything else, you or others could be
badly injured or killed if the vehicle slips off
the jack. Use the jack provided with your
vehicle only for changing a at tire.
If a tire goes at, the next part shows how to use the
jacking equipment to change a at tire safely.
Changing a Flat Tire
If a tire goes at, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your
hazard warning ashers.
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{CAUTION:
Changing a tire can be dangerous. The vehicle
can slip off the jack and roll over or fall on you
or other people. You and they could be badly
injured or even killed. Find a level place to
change your tire. To help prevent the vehicle
from moving:
1. Set the parking brake rmly.
2. Put the shift lever in PARK (P).
3. Be sure the transfer case is in a drive
gear—not in NEUTRAL.
4. Turn off the engine and do not restart
while the vehicle is raised.
5. Do not allow passengers to remain in the
vehicle.
To be even more certain the vehicle will not
move, you can put blocks at the front and rear
of the tire farthest away from the one being
changed. That would be the tire on the other
side, at the opposite end of the vehicle.When you have a at tire, use the following example as a
guide to assist you in the placement of wheel blocks.
The following steps will tell you next how to use the
jack and change a tire.
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Removing the Spare Tire and
Tools (SUT)
The jack is stored in the rear cargo compartment on
the passenger side of the vehicle. The tools for the
jack are stored under the rear passenger’s seat.
To remove the tools:
1. Locate the tools by lifting the driver’s side
second row seat up to expose the oor.
SeeSplit Folding Rear Seat on page 1-8for
more information.
2. Remove the strap from the seat rail. Then carefully
slide the tool bag out from under the seat rail as
shown.
Take care to not pinch the seat cables or electrical
harnesses.
3. Open the tool bag. You will nd the following tools
needed to remove the spare tire and at tire:
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