Cadillac 2011 STS Owner's Manual page 403

number of plies in the sidewall and under the
tread.
manufacturers are required to grade tires based
on three performance factors: treadwear, traction,
and temperature resistance. For more information
see
Maximum load that can be carried and the
maximum pressure needed to support that load.
The type of cord and
Tire
.
tire or temporary use tire has a tread life of
approximately 3,000 miles (5 000 km) and should
not be driven at speeds over 65 mph (105 km/h).
The compact spare tire is for emergency use
when a regular road tire has lost air and gone flat.
If your vehicle has a compact spare tire, see
The compact spare
and
.
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