Is the Measurement for a Bearing Only the Inner Diameter?

Question:

When you give a dimension on a bearing, it’s only one number. Is that for just the inner dimension?

asked by: John S

Expert Reply:

Yes, that is correct. For example the Replacement Trailer Hub Bearing item # 25580 has an inner diameter of 1.750".

If you are trying to replace your trailer's bearings the best way to find the correct replacement is to look on the sides of the bearings for a part number. If yours don't have a visible number you'll need to use a digital caliper like item # PTW80157 to measure your spindle.

I went ahead and attached a helpful graphic below that shows how to measure your bearings and where the bearing number is typically located.

expert reply by: Jerred H