FHWA has new Functional Classification codes.  As described in the memo below, functional classification is now independent of urban/rural boundaries.  The codes are now simplified to 1 to 7 as described below.  The CRS maps on-line (http://www.dot.ca.gov/hq/tsip/hseb/crs_maps/)have been updated in the legend to display the new codes.

FHWA Function Class Memo