By modern safety standards, a Willys Jeep looks like an absolute death trap. How many soldiers died in simple car accidents during the war? How were families informed? Was it the standard "your son died in the line of duty"?
This is not the answer you are looking for but simply based on the main characters in BofB (who where real people) Shifty Powers was seriously hurt in a car accident and Lt Jones dies (in real life) after he exits the show. That's one dead and one almost dead from a short list of people that I remember offhand. My guess is that lots of men died driving the Willys Jeep.