I don't know about food trucks in particular, but I recall reading that restauranteering is a very competitive business, that the average lifetime of a restaurant is something like four years.

kagis

This says five years:

https://www.perrygroup.com/foodservice-expert-overview-on-how-long-restaurants-last/

Of those restaurants and foodservice businesses that made it beyond a year, 70% failed within the next 3 to 5 years. Of those that made it beyond then, 90% remained successful and stayed in business longer than 10 years. There is a more recent article this week in The News Press that reports similar results that our foodservice expert report concluded more than a dozen years ago. This excerpt, along with the full story, shows times have not really changed that much as a restaurant management consultant and what you can learn from these Florida restaurateurs: “According to therestaurantbrokers.com, the average restaurant’s life span is five years with up to 90 percent of independently owned restaurants closing in year one.