Truck overheating towing on long steep grades.

Assuming you are towing in an appropriate gear, people need to realize getting into DV is not that easy. All roads including the road from Beatty, contrary to some opinions is steep and windy. That means lower gears. I have pulled over plenty of times hauling a trailer with my Ford 7.3 to let the engine cool off and also to keep the brakes cool heading to Death Valley. I rarely remember doing that anywhere else.