What is a Center Bore? Hub Centric vs. Lug Centric

The centerbore of a wheel is the size of the machined hole on the back of the wheel that centers the wheel properly on the hub of the car. Centerbores on wheels are typically a standard size by brand or size (measured in inches or mm). Hub sizes vary by vehicle brand and style.

When this hole is machined to exactly match the hub so the wheels are precisely positioned, minimizing the chance of a vibration, it is said that the wheel is “hub centric”.

Some wheels require centering rings that lock into place in the back of the wheel in order to become hub centric and reduce the risk of vibration while driving. This is an acceptable alternative.

If you don’t not have hub centric wheels (lug centric), they should be torqued correctly while the vehicle is still off of the ground so they center properly. The weight of the vehicle can push the wheel off-center slightly while you're tightening them down if left on the ground.

Hub centric rings are manufactured so that when they are installed on a vehicle, the wheels are located directly off of the centre flange of the brake drum or rotor. This is done to insure that the outer beads of the wheel are concentric with the wheel bearings. The result is a much truer, better balanced tire/wheel assembly. This is very important with modern high tech suspension systems.