Tire Sidewall LabelingUseful information about a tire is molded into itssidewall. The examples below show a typical passengervehicle tire and a compact spare tire sidewall.(A) Tire Size: The tire size is a combination of lettersand numbers used to define a particular tire’s width,height, aspect ratio, construction type, and servicedescription. See the “Tire Size” illustration later in thissection for more detail.(B) TPC Spec (Tire Performance CriteriaSpecification): Original equipment tires designed toGM’s specific tire performance criteria have a TPCspecification code molded onto the sidewall. GM’s TPCspecifications meet or exceed all federal safetyguidelines.(C) DOT (Department of Transportation): TheDepartment of Transportation (DOT) code indicates thatthe tire is in compliance with the U.S. Department ofTransportation Motor Vehicle Safety Standards.(D) Tire Identification Number (TIN): The letters andnumbers following DOT (Department of Transportation)code is the Tire Identification Number (TIN). TheTIN shows the manufacturer and plant code, tire size,and date the tire was manufactured. The TIN is moldedonto both sides of the tire, although only one sidemay have the date of manufacture.(E) Tire Ply Material: The type of cord and number ofplies in the sidewall and under the tread.(F) Uniform Tire Quality Grading (UTQG): Tiremanufacturers are required to grade tires based onthree performance factors: treadwear, traction,and temperature resistance. For more information seeUniform Tire Quality Grading on page 5-75.(G) Maximum Cold Inflation Load Limit: Maximumload that can be carried and the maximum pressureneeded to support that load.Passenger (P-Metric) Tire Example5-59
