The sheer size of 18-wheelers – which can be as long as 53 feet and weigh up to 80,000 pounds – is certainly intimidating. Their size makes them more likely to cause serious injuries when involved in a crash. Consider, for example, the fact that large trucks only account for 4 percent of all registered vehicles, yet they account for 8 percent of all vehicles involved in fatal crashes. Or, that when large trucks collide with other vehicles, it is the occupants of those vehicles – not the truck drivers – who are killed or injured 73 percent of the time.