It is number '3' in the picture. The 5th gen Prelude doesn't have the washer like the 4th gen Prelude does. It almost seems like Honda just merged the washer and the nut together for the 5th gen. The washer does have a point in the center of it that fits along a groove on the spindle which I guess keeps the washer from being able to rotate around the spindle on the knuckle. I can't figure out any purpose for the washer other than to provide a spacer. So does anyone know what purpose this washer serves and would it be detrimental if it wasn't used?

 

I don't know why it is keyed with the spindle but as a washer it does distribute the load applied from the nut that holds the wheel bearing together. I would use it or one like it as wheel bearings are important running gear and expensive when they fail.

Pirate