Ford 6.7 diesel warning

We were in Nebraska two days ago on our way home to Florida from Alaska when my F350 diesel suddenly gave an audible alarm and flashed up the message to "STOP SAFELY NOW" . To this point it had performed flawlessly over 14000miles of travel to Alaska and 3 oil/filter/inspections en route from Florida to Alaska and back to Nebraska. I pulled over quickly and tried to get as far off the road into the cornfields as possible. As soon as I engaged park the truck stopped and would not restart. The truck is a 2012 and still covered by warranty so I called Ford Roadside Assistance and a tow truck that loaded the truck on a flatbed and pulled my Airstream 30 behind appeared within about an hour and a half. I was taken 30 miles back to the nearest Ford dealer who diagnosed and repaired the issue early the next day. In the meantime I had more or less figured out the problem using the magic of google (we were fortunate enough to have cell coverage where we broke down). My truck had 51500 miles on it when this occurred. Reading online I found out that failures of the EGT sensors of which there are 4 on my truck are common between 50 and 70000miles and, lo and behold, the standard Ford warranty only covers emissions items up to 50000miles. The sensor failure creates a sudden and disconcerting event and I felt fortunate that we were able to pull up in a reasonably OK location before being totally unable to over the truck/trailer (the dealer can override the close down with his IDS connection). As far as I am aware Ford do not recommend sensor replacement at 50K miles but in my opinion this is the very least they should do.