Cadillac 2007 XLR Owner's Manual page 429

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.
CAUTION:
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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 tires on all four wheels.
CAUTION:
{
If you use bias-ply tires on your 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 your 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 may give an inaccurate low-pressure
warning if non-TPC spec rated tires are installed
on your vehicle. 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 423.
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