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The specifications of car hub include the diameter, width, bolt hole size (PCD), center hole, and offset. Some of these parameters can be visually observed in appearance, some require simple measurement, and some require professional tools for measurement. So how do we determine the size of the wheel hub?

The diameter of the hub, also known as the size of the hub, can be easily seen on the tire. In the tire specifications, such as 225/45R17, 17 refers to the size of the hub, simply put, it is a 17-inch hub. The width of the hub is not visually identifiable, but can be inferred from the tire specifications. For example, in the tire specification 195/60R15, 195 represents the width of the tire. The corresponding width of the hub is generally 6 inches for a 195mm wide tire. Due to different tire manufacturers, a 6-inch wide hub generally corresponds to a tire width of 190-195mm.

The size of the bolt hole, most domestic cars have 4 or 5 bolt holes, while off-road vehicles usually have 6 or 8. How do we know the size of the bolt hole? The size of the bolt hole is an important parameter in wheel hub installation. For 4 bolt holes, you can use a ruler to measure the distance between two diagonal bolts, and that size is commonly referred to as 4x100. For 5 holes, it is a bit more difficult. You can also measure it, and common parameters for 5-bolt holes of cars are 5x100, 108, 112, 120, and 114.3. In different car brands, American brands such as Ford and Chevrolet are mostly 5x108, while Mercedes-Benz, Audi, and Volkswagen are mostly 5x112. BMW and Land Rover are 5x120, and Hyundai, Honda, Toyota, and Nissan are mostly 5x114.3. Most domestic car brands are 5x100. With this information, we can know the parameters without measuring.

The dimensions of the center hole and offset are more professional and require tools for measurement. However, these can be adjusted with the use of spacers or center rings during modification, so actual measurement is not necessary.