BELTS

UTQG (Uniform Tire Quality Grade): A government-mandated tire rating system based on a tire's performance in treadwear durability, traction, and temperature resistance. UTQG ratings are branded on the tire's sidewall. Generally under controlled conditions, the higher the treadwear number (normally between 60-780), the less the tire will wear over time. Traction is based on lettering AA, A, B, C. Having an “AA” means the manufacturer rated tire high for traction. Temperature (A-C) represents how well a tire disperses heat at maximum speeds. An “A” rating means it dissipates heat at a higher speed.

Service Description: A service description is a number and a letter that together describes the tire’s load index and speed rating. This is generally molded into the sidewall of the tire. For instance, using 225/60R/18 99H as an example, the 99H denotes the tire’s service description. (See Load index, and Speed Rating).

Load Range: The maximum weight that the tire is designed to carry; dictated by the tire's construction. Metric passenger type tires are offered with a Standard Load (SL) Rating (up to 35 psi), or Extra Load (XL) Rating (up to 41 psi). LT Metric (truck type) tires are offered with ply ratings of C (8 ply), D (8 ply), and E (10 ply) and at various inflation pressures up to 80 psi.

Tread Depth: Measured in 32nds of an inch, Tread depth measures the top of the tire tread rubber to the bottom of its grooves. Tires should be replaced if worn down to 2/32nds or below.

Speed Rating: A code (A-Z) indicating the maximum speed a tire can carry in relation to a specified load capacity.

*For tires having a maximum speed cpability above 149 mph, a ZR may appear in the size designation. Above 186 mph a ZR must appear in the size designation, including a Y speed symbol in brackets.

Load Index: An assigned numerical code that corresponds to the load carrying capability of a tire. The higher the Load Index number, the greater a tire’s load it can carry.