Cadillac 2011 CTS Coupe Owner's Manual page 403

additional information.
The rubber in tires age over
time. This is also true for the
spare tire, if the vehicle has one,
even if it is not being used. Multiple
conditions affect how fast this
aging takes place, including
temperatures, loading conditions,
and inflation pressure maintenance.
Tires will typically need to be
replaced due to wear before they
may need to be replaced due to
age. Consult the tire manufacturer
for more information on when tires
should be replaced.
Tires age when stored normally
mounted on a parked vehicle. Park
a vehicle that will be stored for at
least a month in a cool, dry, clean
area away from direct sunlight to
slow aging. This area should be
free of grease, gasoline, or other
substances that can deteriorate
rubber.
and Parking for an extended period
for can cause flat spots on the tires
that may result in vibrations while
driving. When storing a vehicle for
at least a month, remove the tires
or raise the vehicle to reduce the
weight from the tires.
GM has developed and matched
specific tires for your vehicle. The
original equipment tires installed
on your vehicle, when it was new,
were designed to meet General
Motors Tire Performance Criteria
Specification (TPC Spec) system
rating. If you need replacement
tires, GM strongly recommends that
you get tires with the same TPC
Spec rating. This way, your vehicle
will continue to have tires that
are designed to give the same
performance and vehicle safety,
during normal use, as the original
tires.
GM's exclusive TPC Spec system
considers over a dozen critical
specifications that impact the
overall performance of your
vehicle, including brake system
performance, ride and handling,
traction control, and tire pressure
monitoring performance. GM's TPC
Spec number is molded onto the
tire's sidewall near the tire size.
If the tires have an all season tread
design, the TPC Spec number will
be followed by an MS for mud
and snow. See
additional information.
GM recommends replacing tires in
sets of four. This is because uniform
tread depth on all tires will help
keep your vehicle performing most
like it did when the tires were new.
, for