All The Numbers On Tires

Do you know what all the numbers on your new & used tires mean? I didn’t .. then I did some research .. and now I’m sharing it with you.

All of the numbers are there for a reason - feel free to take notes if you’d like:

Type of Tire
The letter “P” on your new and used car tires will let the driver know that the used tire is a passenger tire. There are some other specifications like the letters “LT” that mean the tires are for a light truck. The letter “T” is for spare tires - it usually stands for “temporary”.

Width of the Tires
Say there’s a number like “225” printed somewhere on the tire, this means that this is the width of the tires in mm (millimeters). In order to get this measurement, the tire is measured from sidewall to sidewall. Since the entire measure is usually affected by the width of the entire rim, the measurement is used for the used tire when it’s on the premeditated rim size.

Tire’s Aspect Ratio
This is the main number on your usedtires that tells you the height of the tire is called the aspect ratio; it’s measured from the bead to the top of the tread. It’s usually described as a percentage of the total tire width.

When it comes to high performance tires - like some Bridgestone Used Tires - they’ll typically have a lower aspect ratio then other new & used tires that you get from different used tires stores in your area. The main reason why is because the used car tires that have the lowest aspect ratio will provide drivers with a better lateral stability. If a car goes around some random turn, lateral forces are then generated - the tire has to withstand these forces. New & used tires that have a lower profile have shorter and stuffer sidewalls in order to resist cornering forces better.

Construction of Tires
When your Bridgestone Used Tires have the letter “R” on them, this means that the tire was made using radial construction - one of the most common types of tire construction. The older new & usedtires were made using either diagonal bias (D) or bias belted (B) construction. There’s a separate note that will indicate the number of plies that make up the sidewall of both the tire and the tread.

Rim Diameter
This is one of the easiest things to explain: this number is included to specify, measured in inches, the wheel rim diameter that the tire is made for.

Service Description
The service description will typically consist of two things: Load Ratings & Speed Ratings.

-Load Ratings: this is the number that corresponds to the maximum rated load for that specific used tire - the higher the number, the higher the load capacity.

-Speed Rating: the letter that comes after the load rating is what indicates the maximum speed that’s allowed for this specific tire. For example, the letter “S” will usually mean that the used tire can handle speeds of up to 112 mph.

The UTQG (Uniform Tire Quality Grading) will tell you three things:

-Tread Wear: the higher the number is, the longer the tread on the tire will last.

-Traction: all traction on all new & used tires is rated AA, A, B, or C - AA is the top of the line.

-Temperature: all tire temperature ratings are categorized under either A, B, or C. The rating is a measure of how well your new & used tires will disperse of the heat and how well it handles the buildup of heat.

Hope you learned something!