How to Measure Automobile Wheels
- 1). Look straight at the center of the wheel and count the bolt holes in the center of the wheel.
- 2). Place one end of the tape measure next to a bolt hole. Extend the tape to the opposite-side hole, across from the first circle in the bolt pattern radius.
- 3). Take the measurement at the tape measure case. This is the bolt hole diameter measurement.
- 4). Look on the side of one of the automobile tire for a number code. Unless the tire is extremely eroded or decayed, the number code should be readable. Look for codes in a pattern such as 225/50, for example. This is the tire measurement and size. The 225 is the length of the tire and the 50 is the width. Typical measurements are done in millimeters.
- 5). Place the tape measure from one side of the wheel's outer edge and extend it to the opposite side so that the tape measure goes across the center of the tire. Take the measurement in millimeters. Place one end of the tape measure on the tread side of the tire and extend to the other. Take the measurement of this distance in millimeters. Combine the two numbers in the code pattern to get a tape-measure size of the wheel.
