2008 Volvo C30 Owner's Manual - Page 156

6. H : The tire's speed rating, or the maximum speed at which the tire is designed to be driven for extended periods of time, carrying a permissible load for the vehicle, and with correct inflation pressure. For example, H indicates a speed rating of 130 mph (210 km/h). NOTE This information may not appear on the tire because it is not required by law. 7. M+S or M/S = Mud and Snow, AT = All Terrain, AS = All Season 8. U.S. DOT Tire Identification Number (TIN) : This begins with the letters "DOT" and indicates that the tire meets all federal standards. The next two numbers or letters are the plant code where it was manufactured, the next two are the tire size code and the last four numbers represent the week and year the tire was built. For example, the numbers 317 mean the 31st week of 1997. After 2000 the numbers go to four digits. For example, 2501 means the 25th week of 2001. The numbers in between are marketing codes used at the manufacturer's discretion. This information helps a tire manufacturer identify a tire for safety recall purposes. 9. Tire Ply Composition and Material Used: Indicates the number of plies indicates or the number of layers of rubbercoated fabric in the tire tread and sidewall. Tire manufacturers also must indicate the ply materials in the tire and the sidewall, which include steel, nylon, polyester, and others. 10. Maximum Load: Indicates the maximum load in pounds and kilograms that can be carried by the tire. Refer to the vehicle's tire information placard or the safety certification label, located on the B-Pillar or the driver's door or on the inside of the fuel filler door on Canadian models, for the correct tire pressure for your vehicle. 11. Treadwear, Traction, and Temperature grades : See page 176 for more information. 173 07 Wheels and tires Tire designations 12. Maximum permissible inflation pressure: the greatest amount of air pressure that should ever be put in the tire. This limit is set by the tire manufacturer. The tire suppliers may have additional markings, notes or warnings such as standard load, radial tubeless, etc. 174 07 Wheels and tires Glossary of tire terminology Tire terminology Tire information placard : A placard showing the OE (Original Equipment) tire sizes, recommended inflation pressure, and the maximum weight the vehicle can carry. Tire Identification Number (TIN) : A number on the sidewall of each tire providing information about the tire brand and manufacturing plant, tire size and date of manufacturer. Inflation pressure: A measure of the amount of air in a tire. Standard load : A class of P-metric or Metric tires designed to carry a maximum load at 35 psi [37 psi (2.5 bar) for Metric tires]. Increasing the inflation pressure beyond this pressure will not increase the tires load carrying capability. Extra load : A class of P-metric or Metric tires designed to carry a heavier maximum load at 41 psi [43 psi (2.9 bar) for Metric tires]. Increasing the inflation pressure beyond this pressure will not increase the tires load carrying