I would guess its the clutch master or slave. Check the fluid and see if the master is empty. If it is it something blew out and you need a new one. You dont need to remove the trans to change.
97 TJ 4.0, auto, 4.5" RE long arm, 33 " MT/R's on Moabs, 4.10's, 8.8 w/Aussie locker, A to Z rockers, A/A SYE, Warn M8000, Vanco