Originally a classically trained pianist, he was a pioneer in the early use of the electronic organ (Hammond B3) in heavy metal. He is also an avid golfer. In March 1965, he briefly joined The Diplomats before joining The Sparrows in September of that year.
John Kay asked him if he could be known as "Goldy" while riding the bus to Willowdale.
Goldy felt "Goldy Goadsby" would not be right, so in honor of his mother, Dorothy (née) McIntyre, Goldy added the "Mc" to his legal first name, creating his stage name. The band (with various changes) went on to become Steppenwolf and he remained with the group from 1967 to early 1975 when he was fired by Kay.
During Steppenwolf"s hiatus in the early 1970s, he and Steppenwolf drummer Jerry Edmonton formed Manbeast with Rod Prince and Roy Cox of Bubble Puppy, during which time the band penned at least one song that would appear on Steppenwolf"s 1974 release, Slow Flux, Goldy"s last with the band. McJohn helped reform Steppenwolf in 1977 with Nick Saint Nicholas and Kent Henry and played in several incarnations of the band.
He also played with Steve Marriott in a reconstituted version of Humble Pie.
McJohn lives in West Seattle, Washington where he performs and records locally. His solo releases include New Visions, Fugue in Doctorate, Goldy McJohn & Friendz, Rat City in Blue, Secretariat the World on Fire and Osmosis. Goldy now tours with Glen Bui on the "Born To Be Wild 2014-2015 Tour" performing Steppenwolfs Greatest Hits.