Carroll left his colleagues on June 3, 2011, after 31 years and three months behind the wheel. He began his career as a part-time bus driver at the former Snelling Garage, moving to full-time work after 12 years. Career highlights were receiving an award for 30 years of safe driving in 2010 and winning the agency's Roadeo – a safety and skills competition – in the part-time category in 1987. Metro Transit estimates that he served more than 880,000 customers over his years of service. Upon retirement, he planned to engage in his favorite hobby: designing and building unicycles, having already built more than 100.