Tell your friend to try to run a 50/50 blend of water and
antifreeze since, as it was earlier stated, this will raise the BP of the coolant mixture significantly. It will also lubricate the water pump and will slow down corrosion.
Synthetic oil also tends to tolerate heat better than does dyno
oil.
What really amazes me is that
your friend did not just pull over and turn it off.
Bob