Mercedes-Benz SLR McLaren. Operator's Manual.

Operation
Tires and wheels
Tire speed rating
The tire speed rating 6 ( page 272)
indicates the approved maximum speed
for the tire.
Warning! G
Even when permitted by law, never operate
a vehicle at speeds greater than the
maximum speed rating of the tires.
Exceeding the maximum speed for which
tires are rated can lead to sudden tire
failure, causing loss of vehicle control and
possibly resulting in an accident and/or
personal injury and possible death, for you
and for others.
274
i
Tire load rating 5 ( page 272) and
tire speed rating 6 ( page 272) are
also referred to as “service description”.
Summer tires
Index Speed rating
Q up to 100 mph (160 km/h)
R up to 106 mph (170 km/h)
S up to 112 mph (180 km/h)
T up to 118 mph (190 km/h)
H up to 130 mph (210 km/h)
V up to 149 mph (240 km/h)
W up to 168 mph (270 km/h)
Y up to 186 mph (300 km/h)
(Y) above 186 mph (300 km/h)
ZR above 149 mph (240 km/h)
At the tire manufacturer’s option, any
tire with a speed capability above
149 mph (240 km/h) can include a
“ZR” in the size designation (for example:
245/40 ZR18). To determine the
maximum speed capability of the tire,
the service description for the tire must
be referred to. The service description
is comprised of the tire load rating 5
( page 272) and the tire speed
rating 6 ( page 272).
If your tire includes “ZR” in the size
designation and no service
description 5 and 6 ( page 272) is
given, the tire manufacturer must be
consulted for the maximum speed capability.
If a service description 5 and 6
( page 272) is given, the speed capability
is limited by the speed symbol in
the service description.
Example: 245/40 ZR18 97Y.
In this example, “97Y” is the service
description. The letter “Y” designates
the speed rating and the speed capability
of the tire is limited to 186 mph
(300 km/h).