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Inside Diameter: Ensuring the Right Fitment

September 23, 2025

Inside Diameter: Ensuring the Right Fitment

The inside diameter of a wheel is an often-overlooked measurement for the correct fitting of a wheel. Knowing what the measurement means and how it should be interpreted is crucial. Getting it right is important to avoid fitment issues and reduce hassle!

Inside Diameter

measuring the inner diameter using calipers

The inside diameter (ID) of a wheel is the diameter of the hollow center bore of the wheel. This is usually where the axle or bearing can fit within the wheel.

The ID can be measured using calipers or a measuring tape, measuring across the widest part of the hole in the wheel. For the most accurate results, use calipers instead of measuring tape—especially for pallet jack and load wheels that require precision within thousandths of an inch. When measuring inner and outer diameter, keep in mind that wear and tear can make wheel bores appear larger and axles smaller than their original size.

measuring the inner diameter using a tape measure

Using the Inner Diameter

What the ID means depends on whether or not the wheel will need a bearing.

If the wheel has a bearing, the wheel's plain bore ID will match the outer diameter (OD) of the replacement bearing. If the wheel does not have a bearing, the wheel's ID will match the axle's OD.

Final Thoughts

Taking a few extra moments to double check your measurements can save you time, money, and the hassle of returns.

Having trouble measuring your inner diameter? Have questions or need help choosing the right wheel? Contact us or give us a call at 800-345-0425 (Mon-Fri 7:00 AM to 4:30 PM CST)!





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