2007 BMW 6 Series Owner's Manual - Page 204

Wheels and tires Tire identification marks Knowledge of the labeling on the side of the tire makes it easier to identify and choose the right tires. Uniform Tire Quality Grading Quality grades can be found where applicable on the tire sidewall between tread shoulder and maximum section width. For example: Tread wear 200 Traction AA Temperature A Tire size e.g. 245/45 R 18 96 W Nominal width in mm Aspect ratio in Ξ Belted construction - radial Rim diameter in inches Carrying capacity ID-code (not in ZR tires) Speed code letter (in ZR tires before the R) DOT Quality Grades Tread wear Traction AA A B C Temperature A B C All passenger car tires must conform to Federal Safety Requirements in addition to these grades.< Tread wear The tread wear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified government test course. For example, a tire graded 150 would wear one and one-half, 1γ, times as well on the government course as a tire graded 100. The relative performance of tires depends upon the actual conditions of their use, however, and may depart significantly from the norm due to variations in driving habits, service practices and differences in road characteristics and climate. Speed letter T = up to 118 mph/190 km/h H = up to 131 mph/210 km/h V = up to 150 mph/240 km/h W = up to 167 mph/270 km/h Y = up to 186 mph/300 km/h Tire Identification Number Tires with DOT codes meet the guidelines of the US Department of Transportation. DOT code: e.g. DOT xxxx xxx 3406 Manufacturer code for tire make Tire size and tire design Tire age Traction The traction grades, from highest to lowest, are AA, A, B, and C. These grades represent the tire's ability to stop on wet pavement as measured under controlled conditions on specified government test surfaces of asphalt and concrete. A tire marked C may have poor traction performance. The traction grade assigned to this tire is based on straight-ahead braking traction tests, and does not include acceleration, cornering, hydroplaning, or peak traction characteristics.< Tire age The tire's date of manufacture is indicated on the sidewall: DOT ...3406 indicates that a tire was manufactured in week 34 of the year 2006. BMW recommends replacing all tires at least every 6 years, even if some tires may last for 10 years. 202 Online Edition for Part no. 01 41 0 013 312 - © 02/07 BMW AG