Buyers Guide to Tires

Tires: Passenger Vehicles and Light Trucks
Used and New Automobile Tires
What are all of these numbers?!? Tire specs are standardized by the Tire and Rim Association. The purpose of the Tire and Rim Association, Inc., includes the establishment of interchangeability standards for tires, rims and allied parts. There are many specifications to a tire including max load, tread, max pressure, rim width, section width, tread width, overall diameter, and revolutions per mile. But we aren't going to discuss them all. What do you really need to know to buy a tire? The tread depth and the tire size measured by width / ratio / diameter.
How Do I Know What Tire Size I need?
Look in the owner's manual for your vehicle or on the metal tag often found inside the driver's door, glove gepartment door or fuel hatch. Otherwise look on the sidewall of your existing tires.
"P" designates passenger or performance tires. "LT" designates light-trick tires. The example below shows a Passenger tire, 185 width (millimeters), 75 aspect ratio (height/width), R (radial construction), 14 diameter (inches). Towards the end you have 82 load rating and an "S" speed rating. To make things simpler, just match the specs for your vehicle.

Understanding Key Features of a Tire


Temperature ratings - The letter signifies how well a tire resists heat: A is best, B is intermediate, C is acceptable.