Initial Inspection and Diagnostic Overview

In manufacturing the brake rotor, tolerances of the braking surfaces are closely held for the following conditions:
^ Flatness
^ Parallelism
^ Lateral runout
The maintenance of close tolerances on the shape of the braking surfaces is necessary in order to prevent brake roughness or pulsation.
In addition to these tolerances, the surface finish must be held to a specific range. This range is 60 Ra roughness or less. The control of the braking surface finish is necessary in order to avoid the following problems:
^ Hard pedal apply
^ Excessive brake fade
^ Pulls
^ Erratic performance
Control of the surface finish may improve the lining life. Light scoring of the rotor surfaces not exceeding 1.5 mm (0.06 inch) in depth, which may result from normal use, is not detrimental to brake operation.