According to the Federal Motor Carrier Administration (FMCSA), nearly 4,000 people died in trucking accidents in 2012 - up 18% from 2009. But what is being done to ensure better safety on U.S. roads? "Collision Course," a four-part investigative series reported by Eamon Javers, shines a light on the dangers of crashes that involve long-haul trucks. CNBC breaks down the numbers highlighting that 20% of trucks (over 2 million) inspected in 2012 had out of service violations - faulty brakes, bad tires and shouldn't have been on the road. And, nearly 5% of truck drivers (171,000) had enough violations to be pulled from behind the wheel.