He had been in poor health since 2012 when he suffered an aneurysm, according to vintagevinylnews.com.
Salutes quickly appeared online from Dennis Tufano of the Buckinghams and the group The Shadows of Knight.
Originally known as the Starfires, a band from Cleveland that started in the late-50's that included Geraci, Mert Madsen, Richard Kriss, Al Austin and Jim Fox, later of the James Gang, they changed their name to the Outsiders in 1965.
The band signed with Capitol and their first single, Time Won't Let Me, went to number 5 in early 1966 followed by three more top 40 hits, Girl in Love (1966 / #21), Respectable (1966 / #15) and Help Me Girl (1966 / #37).
After the Outsiders broke up, Geraci formed a new version as The Outsiders Featuring Sonny Geraci and released a few singles on Bell but, after a legal battle, he was forced to change the band's name to Climax.
This band's biggest hit, Precious and Few, was originally recorded in 1970 but reworked by producer Larry Cox (Jefferson Starship). The record company didn't have a lot of confidence in the record so they test marketed it in Hawaii for six months. Precious and Few began to gain traction in the eastern U.S. before eventually breaking nationwide and going to number 3 in 1972.
Climax only had one other charting song, Life and Breath (1972 / #52 Pop / #15 Adult Contemporary). In total, they released nine singles under both the Outsiders and Climax names and had a number of other tracks in the vaults that were never used on a second album. They disbanded in 1975.