Measurement & Verification

Wheel width is the distance between the wheel’s tire bead-seat surfaces, not the full distance across its outer lips. Getting that distinction right matters: width, together with o...

Center-cap clearance depends on two things: how far the cap extends behind the wheel’s mounting face, and how far the vehicle’s hub or axle hardware projects beyond the hub’s wheel...

What you need to measure–and why The vehicle hub diameter is the outside diameter of the raised cylindrical pilot on the hub. That pilot fits inside the wheel’s center bore and hel...

A hub-centric ring must match two separate diameters: its outside diameter (OD) fits the wheel’s center bore, and its inside diameter (ID) fits over the vehicle’s hub pilot. Measur...

An OEM wheel part-number lookup can identify a wheel’s original application and often its basic specifications, but the number alone is not always enough to prove fitment. Part num...

A lug-nut thread test should confirm the nut’s nominal diameter, thread pitch, and thread form without forcing it onto the wheel stud. A nut that appears close enough can cross-thr...

Adding a wheel spacer reduces the amount of wheel-stud thread available to the lug nut. Before fitting one, measure the stud length and verify the actual thread engagement with the...

What a 6-lug PCD measurement tells you PCD, or pitch circle diameter, is the diameter of the imaginary circle passing through the centers of all six lug holes. It is usually writte...

What a 4-lug PCD measurement tells you PCD means pitch circle diameter. It is the diameter of the imaginary circle passing through the centers of all four lug holes. It is usually ...

Why measure actual tire diameter and circumference? The size printed on a tire sidewall is a nominal designation, not a guarantee of the tire’s exact dimensions after mounting. Two...