Cadillac STS 2011 Owner's Manual page 420

Winter tires with the same speed rating as your
original equipment tires may not be available for
H, V, W, Y and ZR speed rated tires. If you choose
snow tires with a lower speed rating, never
exceed the tire's maximum speed capability.
WARNING:
Mixing tires could cause you to lose control while
driving. If you mix tires of different sizes (other
than those originally installed on your vehicle),
brands, or types (radial and bias-belted tires), the
vehicle may not handle properly, and you could
have a crash. Using tires of different sizes (other
than those originally installed on your vehicle),
brands, or types may also cause damage to your
vehicle. Be sure to use the correct size, brand,
and type of tires on all wheels. It is all right to
drive with your vehicle's compact spare
temporarily, it was developed for use on your
vehicle. See Compact Spare Tire on page 6 105.
WARNING:
If you use bias-ply tires on the vehicle, the
wheel rim flanges 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 the
vehicle.
If you must replace your vehicle's tires with those
that do not have a TPC Spec number, make sure
they are the same size, load range, speed rating,
and construction type (radial and bias belted tires)
as your vehicle's original tires.
Vehicles that have a tire pressure monitoring
system could give an inaccurate low pressure
warning if non TPC Spec rated tires are installed
on it. Non TPC Spec rated tires may give a
low pressure warning that is higher or lower
than the proper warning level you would get with
TPC Spec rated tires. See Tire Pressure Monitor
System on page 6 60 .
6-69