2010 Mercedes GLK-Class Owner's Manual - Page 243

Winter driving Rim A metal support for a tire or a tire and tube assembly upon which the tire beads are seated. 241 Tread The portion of a tire that comes into contact with the road. Sidewall The portion of a tire between the tread and the bead. Treadwear indicators Narrow bands, sometimes called "wear bars" that show across the tread of a tire when only 1/ in (1.6 mm) of tread remains. 16 TWR (Tongue Weight Rating) Maximum permissible weight on trailer tongue. Unique identifier which facilitates efforts by tire manufacturers to notify purchasers in recall situations or other safety matters concerning tires and gives purchasers the means to easily identify such tires. The TIN is comprised of "Manufacturer's identification mark", "Tire size", "Tire type code" and "Date of manufacture". Uniform Tire Quality Grading Standards A tire information system that provides consumers with ratings for a tire's traction, temperature and treadwear. Ratings are determined by tire manufacturers using U.S. government testing procedures. The ratings are molded into the sidewall of the tire. Tire ply composition and material used This indicates the number of plies or the number of layers of rubber-coated fabric in the tire tread and sidewall. Tire manufacturers also must indicate the ply materials in the tire and sidewall, which include steel, nylon, polyester, and others. Vehicle maximum load on the tire Load on an individual tire that is determined by distributing to each axle its share of the maximum loaded vehicle weight and dividing it by two. Tire speed rating Part of tire designation (speed symbol); indicates the speed range for which a tire is approved. Winter driving General information Have your vehicle winterized at an authorized Mercedes-Benz Center. Total load limit Rated cargo and luggage load plus 68 kilograms (150 lb) times the vehicle's designated seating capacity. Winter tires G Warning! Winter tires with a tread depth of less than 1/ in (4 mm) must be replaced. They are no 6 longer suitable for winter operation. Traction The adhesive friction of a tire on a surface on which it moves. The amount of grip provided. Z Operation TIN (Tire Identification Number)