I'm new to this so be gentle. So the engine never overheated, the low coolant sensor triggered an overheat warning. Wouldn't a fault code be generated to tell you this. Shame on Cummins for putting you through this by connecting the low coolant sensor to the overheat warning.
'07 American Tradition 40Z Cummins 400 ISL
Towing a '14 Honda CRV