so you're going to follow IDOT's classification, then? you've got a lot of US routes that need downgrading, then. lots of 34, 52, 6 are shown as minor arterials by IDOT.

or you're going to use street view?
compare
- US 34 east of orchard (https://www.google.com/maps/@41.6831415,-88.3613472,3a,75y,273.26h,88.1t/data=!3m6!1e1!3m4!1s46RDUd-Zi62Oy7mamQ3XWg!2e0!7i16384!8i8192?entry=ttu)
- IL 31 north of Oswego (https://www.google.com/maps/@41.6905577,-88.3551076,3a,60y,11.39h,88.96t/data=!3m6!1e1!3m4!1sqeLC1GolJYhGDE1v4kzmFg!2e0!7i16384!8i8192?entry=ttu)
- Orchard (https://www.google.com/maps/@41.6926215,-88.3803817,3a,60y,90t/data=!3m6!1e1!3m4!1sQ7_gAHd9LcqrgzDULQApeQ!2e0!7i16384!8i8192?entry=ttu)

by what measure should these three roads be classed the same? your classification is not consistent on physical characteristics, nor IDOT classification, nor us / state route status, nor local opinion.