Maserati Gransport Owner's Manual page 130

Temperature
The temperature grades are "A" (the
highest), "B", and "C", representing
the tire's resistance to the generation
of heat and its ability to dissipate heat
when tested under controlled
conditions on a specified indoor
laboratory test wheel. Sustained high
temperature can cause the material of
the tire to degenerate and reduce tire
life, and excessive temperature can
lead to sudden tire failure. The grade
"C" corresponds to a level of
performance which all passenger car
tires must meet under the Federal
Motor Safety Standard No. 109. Grades
"B" and "A" represent higher levels of
5
performance on the laboratory test
wheel than the minimum required by
law.
The temperature grade for
this tire is established for a
tire that is properly inflated
and not overloaded. Excessive speed,
underinflation, or excessive loading,
either separately or in combination,
can cause heat buildup and possible
tire failure.
130 Tires
Winter tires
These tires are specially designed for
driving on snow and ice and are fitted
to replace the ones supplied with the
car.
Only use winter tires of the
prescribed dimensions and
brand.
Your Authorized Maserati Dealer is
available to provide suggestions as to
the types of tires most suited to the use
foreseen.
For the type of tires to use, inflation
pressures and relative specifications
for winter tires, carefully follow the
indications found in the "Capacities
and Technical Specifications" chapter.
The features of these tires are
markedly reduced in winter when
tread depth is less than 0.16 in (4 mm).
In this case, they should be replaced.
The specific features of the winter tires
lead to lower performance under
normal environmental conditions or
on long highway trips, compared to
the standard tires.
Therefore, their use should be limited
to the performance for which they
have been type-approved.
Fit identical (manufacturer
and tread) tires on all four
wheels, in order to help
ensure safe driving, braking and good
maneuverability.
Remember that the direction
of tire rotation should not be
reversed.