The trucks are being tested in California and other states.
More than 4 % of all registered vehicles are large trucks.
Drivers are now limited to driving no more than 70 hours a week whereas trucks would be on the road longer.
The driver-less trucks would save over 500 million gallons of fuel or the equivalent of a 1 billion dollars per year.
Uber is involved in developing the science, so is General Motors, and Google.
The big issue will be safety. Will they perform as promised or will they be dangerously disruptive.