Porsche Boxster Owner's Manual page 252

Snow tires
For a better grip on snow and ice, use radial M+S
tires with studs. Check with your local Motor
Vehicle Bureau for possible restrictions.
Danger!
Risk of loss of control and damage to the
vehicle as well as serious personal injury or
death. The standard tires prole and rubber
mixture are optimized for wet and dry driving
conditions, and may not prove favorable for
snow conditions.
Therefore install M+S tires before driving in
such conditions.
Before mounting snow tires, consult with
your Porsche dealer. He has the technical
information necessary to advise you on wheel
and tire compatibility.
Snow tires should have the same load capacity as
original equipment tires and should be mounted on
all four wheels. Snow tires with studs should be run
at moderate speeds when new in order to give the
studs time to settle.
250
Practical Tips, Emergency Service
Danger!
Tires with badly worn treads and studs are
very dangerous and could cause accidents
resulting in serious personal injuries or death.
Make sure they are replaced immediately.
Do not drive a vehicle equipped with snow
tires at prolonged high speed. Snow tires
do not have the same degree of traction on
dry, wet or snowfree roads as a normal tire.
Furthermore, snow tires wear rapidly under
these conditions.
Comply with all state and local laws governing
snow tire and tread depth requirements.
Danger!
Risk of accident and serious personal injury
or death due to excessive speed.
Always check the maximum speed rating on
the tire sidewall on any tire on the vehicle.
Never exceed the maximum speed rating of
the tires.
Fit winter tires to both axles well before the
cold season begins. Your authorized Porsche
dealer will be pleased to advise you.
Maintenance note
We recommend fitting winter tires on the vehicle at
temperatures below 45°F (7°C ).
Winter tires lose their traction capability when their
tread depth falls below 5/32 in. (4 mm).