They don’t pay by the hour. They’ve always pay by the mile. So if you’re working for Heartland Express and stuck in one of those notorious Iowa traffic jams, you’re not getting paid anything.
OTH, few trucks in Iowa are doing only 55 mph.
Actually, I do know of at least one company that pays by the hour, most of their hauls have been one day out and back and as of a couple of years ago the drivers were being paid fifteen dollars an hour to drive old, uncomfortable day-cab trucks and they were not paid overtime rates, just straight fifteen dollars an hour regardless of hours and most days were well over eight hours.