Porsche 928S 1983 Driver Manual page 56

Water reservoirs
To ensure the function of the screen and
headlight washers under frost conditions,
anti-freeze should be added to the water. A
mixture of one part household spirit to three
parts water also works very well.
Winter tyres and snow chains
Due to the reduced effectiveness of sum-
mer tyres in winter we recommend the fitt-
ing of special winter tyres when snow and
ice are expected.
If M + S tyres are used in the winter, they
must be fitted to all 4 wheels. Be acquainted
with the different laws in different lands gov-
erning maximum speeds with these tyres.
54
Snow chains can only be mounted on the
driving wheels, and only the fine link chains
recommended by Porsche for the normal
series tyres should be used. This ensures
that the clearance between the wheel and
wheelhouse is maintained. However, note
the chain manufacturers recommendations.
Your authorized dealer will be pleased to
advise you in choosing the appropriate win-
ter tyres and snow chains.
Additional equipment
It can be helpful during winter to keep a
handbrush and scraper in the vehicle, to
clear the screens of ice and snow, as well as
a board to put under the jack and some dry
sand to help traction when pulling away on
icy slopes.