Factual error: When Llewyn is driving back to NYC from Chicago, he passes a couple signs stating that Akron, OH, is at the next exit off the highway, on US Route 80. US 80 passes exclusively through the South, from Dallas to the Atlantic Ocean in Georgia, and doesn't even come remotely close to Ohio. (01:13:58)
Suggested correction: It's Interstate 80, which does pass through Ohio, not Route 80.
The mistake is correct. It's the US Route 80 sign which has black letters on the white shield. An I-80 sign would have white letters on a red and blue shield.