In 1972, Grand Funk fired Knight, a move which initiated a protracted legal battle. The band eventually hired John Eastman, Paul McCartney's brother-in-law, to handle business matters. At the end of the year, the group added keyboardist Craig Frost for Phoenix. The following year, they officially dropped "Railroad" from their name and issued the Todd Rundgren-produced We're an American Band, which spawned a #1 hit single in the title track.
In 1974, Grand Funk released the more pop-based Shinin' On, which included another chart-topper in their cover of Little Eva's "The Locomotion." Grand Funk's version marked only the second time in history that a remake of a #1 song hit the top. All the Girls in the World -- Beware!! (1974), which spawned the #3 "Some Kind of Wonderful," was the last hit album for Grand Funk.
Grand Funk announced their dissolution in 1976, but reconsidered and came back later that year with the Frank Zappa-produced Good Singin', Good Playin'. The following year, Brewer and Schacher formed a new band, Flint, effectively ending Grand Funk. Flint's eponymous debut album wasn't a big success, nor were Farner's solo efforts.
In 1981, Brewer and Farner resurrected Grand Funk for an album that cracked the Billboard albums chart. Two years later, they split again and Brewer decided to join rocker Bob Seger's Silver Bullet Band.