How To Guides

Trailer Parts How To Guides - Trailer Tire Terms

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  • Design Rim Width: "Design Rim Width" is the specific rim width assigned to each tire size designation to determine basic tire dimensions.
  • Section Width: "Section Width" is the maximum width of a new tire.
  • Overall Diameter: "Overall Diameter" is the diameter of an inflated tire at the most surface of the tread.
  • Maximum Load Capacity: "Maximum Load Capacity" is the maximum weight a tire is designed to carry under standard use conditions.
  • Load Identification: Load Range with a letter (A, B, C, etc.), Standard Load and Extra Load are used to identify a given size tire with its load and inflation limits when used in a specific type of service.
  • Ply Rating: is a term used to identify a given tire with its maximum recommended load when used in a specific type of service. It is an index of tire strength and does not necessarily represent the number of cord plies in the tire.
  • Static Load Radius: "Static Load Radius" is the dimension from the bottom of the tire to the center line of an axle when the tire is loaded at its rated capacity.
  • How The Tire Part Number System Works: The Part Numbers incorporate tire sizes and descriptions to allow you to easily determine the tires you need to order. For example, part numbers 7516BD and P215-75-R15BB can be interpreted as follows (see diagram)

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