Thanks, we’re collecting resources like this on the OSM Wiki. It’ll come in handy once we’re ready to take some focus off the Interstate system.
Yes, AASHTO is the authority on those designations. They decommissioned U.S. 66 piecemeal as various Interstates bypassed it. The remaining segments from Missouri through Arizona were decommissioned in June 1985. (The AARoads Wiki maintains a comprehensive index of AASHTO minutes for determining when a U.S. Route, Interstate highway, or U.S. Bicycle Route changed in any significant way, though the minutes can often lack detail or context.)
TIGER 2005 (the version we imported in 2008) had a lot of very outdated names. Even today, the road names in TIGER often confuse U.S. Highways with state highways or county highways, especially if you look in the name_1=*
and name_2=*
keys. Street names and colloquial usage can also lag behind the official route designations by many years.