Never  allow the wheels to lock up during braking.
Snow tires, studded tires *
Tires for winter use:
Owners who live in or  regularly  travel through  areas with sustained  periods of snow or  icy driving conditions
are strongly advised to fit  suitable winter tires to help retain the highest degree of traction. It is important to
install  winter tires on all four wheels  to help retain traction during cornering, braking, and  accelerating. Failure to do
so could reduce traction to an  unsafe level  or adversely affect handling. Volvo does not recommend tire rotation.
However, as with any  other radial tires, if rotated, the tires must  be  kept on the same side of the car so that they
revolve in the same direction as before rotation.
Volvo recommends  195/65 R15 snow tires on non-turbo models. Turbo models should be equipped  with 205/55
R16 snow tires on all four wheels (215/65 R16 tires should be used  on the XC70).
Winter tires wear  more quickly on dry roads in warm weather. They should be  removed when the winter driving
season has ended.
Studded tires should be  run-in 300-600 miles (500-1000 km) during which  the car should be  driven as smoothly as
possible to give the studs the opportunity to seat properly in the tires. The tires should have the same rotational
direction throughout their entire lifetime. In other words,  if you wish to rotate the wheels, make sure that the same
wheels are always on the same side of the car.
NOTE: Please consult state or provincial regulations  restricting the use of studded winter tires before installing such
tires.
* Where permitted. 
pg. 110 Wheels and tires
Tire pressure  label
Checking and correcting tire pressure
Check the tire pressure regularly.
The tire pressure should be  corrected only when the tires are cold.
With warm tires, correct only when the pressure is too low. The tire temperature rises after driving just  a  few miles.
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