GM Service Manual Online
For 1990-2009 cars only

Centerline Description for Chevrolet Astro - 4WD 2003

A centerline is an imaginary vertical plane that is perpendicular to the length of the datum plane through the center of the vehicle. The centerline is any line drawn through the center of the vehicle's datum. The symbol for centerline is CL.

Refer to Datum Description for more information about the datum plane.