Tires & Wheels

Tire Size

An example of the meaning of the different markings in a tire size is given below for a tire size of 225/45 R17 94H:

225 - Tire section width, mm

45 - Aspect ratio, i.e. the section height as a percentage of the section width

R - Radial ply

17 - Wheel rim diameter 17 in at bead seats

94 - Tire load index

H - Speed rating

Tire Width

The three-digit number indicates the tire section width in millimeters from sidewall to sidewall.

Aspect Ratio

A two-digit number that indicates the tire height-to-width measurements. For example, if the tire size aspect ratio is “55”, as shown in item “C” of the illustration, it would mean that the tire´s sidewall is 55% as high as it is wide. Belt Rating: A letter code is used to indicate the type of ply construction in the tire. The letter “R” means radial ply construction; the letter “D” means diagonal or bias ply construction; and the letter “B” means beltedbias ply construction.

Rim Diameter

Diameter of the wheel in inches.

Tire load indices

The load range represents the load carry capacity a tire is certified to carry.

91 - Tire approved for max. 1355 lbs. (615 kg)

93 - Max. 1433 lbs. (650 kg)

94 - Max. 1477 lbs. (670 kg)

95 - Max. 1521 lbs. (690 kg)

97 - Max. 1609 lbs. (730 kg)

Speed ratings

The maximum speed that a tire is certified to carry a load. Speed ratings range from “A” to “Z”.

Q - Tire approved for speeds up to 100 mph (160 km/h)

S - Max. 112 mph (180 km/h)

T - Max. 118 mph (190 km/h)

H - Max. 130 mph (210 km/h)

V - Max. 149 mph (240 km/h)

W - Max. 168 mph (270 km/h)

Y - Max. 186 mph (300 km/h)

Department of Transportation (DOT)

The Department of Transportation (DOT) code indicates that the tire is in compliance with the U.S. Department of Transportation Motor Vehicle Safety standards.

Tire Identification Number (TIN)

The letters and numbers following DOT code are the Tire Identification Number (TIN). The TIN shows the manufacturer and plant code, tire size, and date the tire was manufactured. The TIN is molded onto both sides of the tire.

DOT aa bb cccc dddd

A. Manufacture's Identification Mark

B. Tire Size

C. Tire Type Code

D. Date of Manufacturing

Tire Ply Material

The type of cord and number of plies in the sidewall and under the tread.

Date Manufactured

The date the tire was manufactured.