2011 Mercedes R-Class Owner's Manual - Page 340
2011 Mercedes R-Class Manual
Page 340 highlights
338 Tire labeling For further information on the load bearing index, see load index (Y page 339). Speed index: speed index B specifies the approved maximum speed of the tire. The service specifications consists of load bearing index A and speed index B. RIf the size description of your tire includes "ZR" and there are no service specifications, ask the tire manufacturer in order to find out the maximum speed. If a service specification is available, the maximum speed is limited according to the speed index in the service specification. Example: 245/40 ZR18 97 Y. In this example, "97Y" is the service specification. The letter "Y" represents the speed index and the maximum speed of the tire is limited to 186 mph (300 km/h). REvery tire that has a maximum speed above 186 mph (300 km/h) must have "ZR" in the size description and the service specification must be given in brackets. Example: 275/40 ZR 18 (99 Y). The speed index "(Y)" shows that the maximum speed of the tire is above 186 mph (300 km/h). Ask the tire manufacturer to find out the maximum speed. All-weather tires and winter tires Index Speed rating G Warning 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 serious personal injury and possible death, for you and for others. Regardless of the speed index always observe the speed limits. Drive carefully and adapt your driving style to the traffic conditions. Tires and wheels Summer tires Index Q R S T H V W Y ZR...Y ZR...(..Y) ZR Speed rating up to 100 mph (160 km/h) up to 106 mph (170 km/h) up to 112 mph (180 km/h) up to 118 mph (190 km/h) up to 130 mph (210 km/h) up to 149 mph (240 km/h) up to 168 mph (270 km/h) up to 186 mph (300 km/h) up to 186 mph (300 km/h) above 186 mph (300 km/h) above 149 mph (240 km/h) Q M+S43 up to 100 mph (160 km/h) T M+S43 up to 118 mph (190 km/h) H M+S43 up to 130 mph (210 km/h) V M+S43 up to 149 mph (240 km/h) ROptionally, tires with a maximum speed of over 149 mph (240 km/h) may have "ZR" in the size description depending on the manufacturer (e.g. 245/40 ZR 18). i Not all tires that have the M+S identification offer the driving characteristics of winter tires. Winter tires have, in addition to the M+S identification, the i snow flake symbol on the tire sidewall. Tires with this identification fulfill the requirements of the Rubber Manufacturers Association (RMA) and the Rubber Association of Canada (RAC) regarding the tire traction on snow and 43 or M+Si for winter tires.