Bolt Pattern/Pitch Circle Diameter (PCD)
PCD (Pitch Circle Diameter) is the measurement of the diameter of the imaginary circle drawn through all of the wheel bolts or studs on a wheel. It is also known as the 'bolt circle'.
A wheel's PCD is usually displayed after the number of studs, separated by a slash. Hence a 'pcd' of 5/120 means that the wheel has five studs, and a pitch circle diameter of 120mm. A 'pcd' of 4/114.3 means the wheel is four stud with a pitch circle diameter of 114.3mm.
Measuring the PCD of a 5 stud wheel is a tricky business. It is much easier to determine the PCD by checking the manufacturers' original specifications or by checking our PCD reference guide for each model. It is possible to roughly measure the PCD of a 4 stud wheel, as the pitch circle diameter is the same as the distance between two opposite bolt centres.
Different cars have different PCDs, but often similar cars within the same manufacturers group have the same PCD. Many of the VW Golf-sized cars in the VAG range have the same PCD and other wheel dimensions, meaning that wheels are often interchangeable between these cars.
The PCD has to do with the sizing of the diameter of a circle that the lug holes create. The center of every bolt/lug lies on the circumference of a circle that they create. PCD is usually measured in millimeters (mm).
For example, the 5x114.3 (or 5x4.5 in inches) PCD that our 3G TLs use means that there are 5 lug holes, with a pitch circle diameter of 114.3mm or 4.5in.
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