Vehicles with P265/70R17 or P275/55R20 size tires
require in ation pressure adjustment when driving the
vehicle at speeds of 100 mph (160 km/h) or higher.
Set the cold tire in ation pressure to 3 psi (20 kPa)
above the recommended cold tire pressure shown on
the Tire and Loading Information label.
When you end this high-speed driving, return the tires
to the cold in ation pressure shown on the Tire and
Loading Information label. SeeLoading the Vehicle on
page 4-32andInflation - Tire Pressure on page 5-73.
Dual Tire Operation
When the vehicle is new, or whenever a wheel, wheel bolt
or wheel nut is replaced, check the wheel nut torque after
100, 1,000 and 6,000 miles (160, 1 600 and 10 000 km)
of driving. For proper torque and wheel nut tightening
information, seeRemoving the Spare Tire and Tools on
page 5-93.The outer tire on a dual wheel setup generally wears
faster than the inner tire. Your tires will wear more
evenly and last longer if you rotate the tires periodically,
seeTire Inspection and Rotation on page 5-81. Also
seeScheduled Maintenance (Gasoline Engine) on
page 6-4.
{CAUTION:
If you operate your vehicle with a tire that is badly
underin ated, the tire can overheat. An overheated
tire can lose air suddenly or catch re. You or
others could be injured. Be sure all tires (including
the spare) are properly in ated.
SeeInflation - Tire Pressure on page 5-73, for
information on proper tire in ation.
5-75
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 the 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 the 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.
Whenever a wheel, wheel bolt or wheel nut is replaced
on a dual wheel setup, check the wheel nut torque after
100, 1,000 and 6,000 miles (160, 1 600 and 10 000 km)
of driving. For proper torque, see “Wheel Nut Torque”
underCapacities and Specifications on page 5-129.
SeeChanging a Flat Tire on page 5-92for more
information.
5-89
{CAUTION:
Incorrect or improperly tightened wheel nuts can
cause the wheel to come loose and even come
off. This could lead to a crash. If you have to
replace them, be sure to get new original
equipment wheel nuts. Stop somewhere as soon
as you can and have the nuts tightened with a
torque wrench to the proper torque speci cation.
SeeCapacities and Specifications on page 5-129
for wheel nut torque speci cation.
Notice:Improperly tightened wheel nuts can lead
to brake pulsation and rotor damage. To avoid
expensive brake repairs, evenly tighten the wheel
nuts in the proper sequence and to the proper
torque speci cation. SeeCapacities and
Specifications on page 5-129for the wheel nut
torque speci cation.12. Tighten the nuts rmly in a crisscross sequence as
shown by turning the wheel wrench clockwise.
When you reinstall the regular wheel and tire, you must
also reinstall either the center cap, or bolt-on hub cap,
depending on what your vehicle is equipped with. For
center caps, place the cap on the wheel and tap it into
place until it seats ush with the wheel. The cap only
goes on one way. Be sure to line up the tab on the center
cap with the indentation on the wheel. For bolt-on hub
caps, align the plastic nut caps with the wheel nuts and
then tighten by hand. Then use the wheel wrench to
tighten.
5-105
