Pretty much on the money. Traffic Enforcement handles Lake Shore Drive and the Chicago Skyway. In addition they also conduct the roadside safety checks in the districts , D.U.I. checkpoints things of this nature. Traffic Enforcement will be handling the "new" push for radar enforcement hot spots. What get's confusing is you may also hear a "traffic car" on the Zones. They basically handle accidents and parking complaints district-wide only. They are not assigned to the Traffic Enforcement Section. (3200 Series Units).
Public Transportation (4100 Series Units) handles the CTA. Referred to as Mass Transit Officers. They have Canine Units assigned to them as well. Their Beat Number designations seem to frequently change, but currently use 4610-4639A-D. Third number designates the watch. The letter designations at the end are the officers, without are Sergeants. They are currently assigned to the Special Operations Section, but you must keep up as it seems to change frequently. All are assigned to operate on City-Wide 1, however can also utilize the Zones.
