At age 12 Grenadier began formal study of the acoustic bass, learning from local jazz bass players Chris Poehlor, Paul Breslin, and Frank Tusa and later classical bassists Michael Burr and Stephen Tramontozzi. At 16, Grenadier had a busy career playing in the San Francisco Bay Area with both local musicians and those traveling through town in need of a bass player. These musicians included Harvey Wainapel, Bobby Hutcherson, Joe Henderson, Larry Vuckovitch, Eddie Henderson, Bruce Forman, Eddie Marshall, Vince Lateano, George Cables and Donald Bailey, Toots Thielmans, Johnny Griffin, Charles McPherson and Frank Morgan, among others.