load capacity PONTIAC GTO 2004 User Guide

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 ination 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
ination 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
inflation pressure when operating your vehicle under
high-speed conditions.
Tire Size: 235/40ZR18 91W Recommended Cold
Tire Ination 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 inflation pressure shown on the tire and loading
information label.
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Buying New Tires
To find out what kind and size of tires you need, look at
the Tire and Loading Information label. For more
information about this label and where to find it, see
Loading Your Vehicle on page 4-30.
Make sure the replacements are the same size,
load capacity, speed rating and construction type
(bias, bias-belted or radial) as your original tires.
{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes
or types (radial and bias-belted tires), the
vehicle may not handle properly, and you
could have a crash. Using tires of different
sizes may also cause damage to your vehicle.
Be sure to use the same size and type tires on
all wheels. It’s all right to drive with your
compact spare temporarily, it was developed
for use on your vehicle. See “Compact Spare
Tire” in the index.
{CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rim anges could develop cracks after
many miles of driving. A tire and/or wheel
could fail suddenly, causing a crash. Use only
radial-ply tires with the wheels on your vehicle.
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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.
SeeChanging a Flat Tire on page 5-71for more
information.
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