There is no reason that your engine could not idle until the fuel tank ran dry....
Engines that do a lot of idling are taxis; the engines generally last longer than most cars because the engines are always at operating temperature.
Modern hemi’s( 5.7) have known issues idling extended periods of time.
Seen tons of cam/ lifter issues, and lots of idling is pretty well acknowledged as a big culprit.
Very common issue.
