It was as a songwriter that Loudermilk made his mark. In 1963 he wrote another all-time hit for George Hamilton IV, "Abilene". Working out of country music capital Nashville, Tennessee, Loudermilk became one of the most productive songwriters of the 1960s and 1970s, penning country and pop music hits for the Everly Brothers, Johnny Tillotson, Chet Atkins, the Nashville Teens, Paul Revere & the Raiders, Johnny Cash, Marianne Faithfull, Stonewall Jackson, Sue Thompson and others. For example, he wrote "The Pale Faced Indian", later known as "Indian Reservation", a hit in the 1970s, and "Tobacco Road", a hit in the 1960s and 1970s for, among others, the Nashville Teens, Blues Magoos, Eric Burdon & War, and David Lee Roth. "Midnight Bus" was recorded by several singers, and he commented that the best was by Betty McQuade in Melbourne, Australia.