Did Mark Farner ever drum for Grand Funk Railroad?

Yes, but with Don Brewer on stage, drumming along with him in Grand Funk. Mark was a guitarist from teenage years, and also played harmonica, piano/organ , drums, and bass. He joined Terry Knight and the Pack as a bass player to get in the band, although he was a guitarist. He later became the vocalist and lead guitarist when Terry and Kurt quit at different times. Photo of Mark playing drums with Grand Funk next to Don Brewer, standing with snare drum, are after page 96 and before page 97, in Bill Cooks photo in the book, "An American Band- the story of Grand Funk Railroad" by Billy James. The book claims that it is a 1970 concert, but since seeing GFR several times in 1970 personally, Mark was still playing his famous green Messenger guitar and even at least April 15, 1971 when seen at the San Diego Sports Arena. Mark is playing a Gibson SG in these photos, so they are from 1971 or 1972. Also, Mark wasn't playing drums with Donnie in 1970.