DL 3879 then DL 1084 at Detroit
Cleveland → Detroit → Chicago O'Hare
Timetable, Detroit time
11:23DL 3879 from Cleveland at the gate
17:56DL 1084 to Chicago O'Hare leaves the gate
6 h 33 apart on the timetable
The last days
DL 3879 and DL 1084 weren’t both flown 15 min to 12 h apart in the last 21 days.
Statistics from past flights, not live flight information. Always check times and your connection with your airline, and don’t base travel or booking decisions on these numbers.