High Speed Operation
{CAUTION:
Driving at high speeds, 100 mph (160 km/h) or
higher, puts an additional strain on tires.
Sustained high-speed driving causes
excessive heat build up and can cause sudden
tire failure. You could have a crash and you or
others could be killed. Some high-speed rated
tires require in¯ation pressure adjustment for
high speed operation. When speed limits and
road conditions are such that a vehicle can be
driven at high speeds, make sure the tires are
rated for high speed operation, in excellent
condition, and set to the correct cold tire
in¯ation pressure for the vehicle load.Vehicles equipped with 245/45ZR17 95W size tires, do
not require additional air pressure for high-speed
operation. If your vehicle has 235/40ZR18 91W size
tires, use the following chart to determine the cold tire
in¯ation pressure when operating your vehicle under
high-speed conditions.Tire Size: 235/40ZR18 91W Recommended Cold
Tire In¯ation Pressure for High Speed Operation
Occupant and Cargo
Weight:
470 lbs (210 kg) or lessOccupant and Cargo
Weight:
Up to 740 lbs (330 kg)
(Vehicle Capacity
Weight)
Front
TiresRear Tires Front Tires Rear Tires
36 psi
(250 kPa)36 psi
(250 kPa)39 psi
(270 kPa)44 psi
(300 kPa)
When you end high-speed driving, return the tires to the
cold in¯ation pressure shown on the tire and loading
information label.
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2006 - Pontiac GTO Owner Manual
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 may need to
be checked. If you notice your vehicle vibrating when
driving on a smooth road, your tires and wheels
may need to be rebalanced. See your dealer 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 if any of these conditions exist.
Your dealer 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
or wheel nuts, replace them only with new GM
original equipment parts. This way, you will be sure to
have the right wheel, wheel bolts and wheel nuts
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.
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.
See
Changing a Flat Tire on page 5-69for more
information.
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2006 - Pontiac GTO Owner Manual
