I have a 1994 gmc sierra 1500 5.0 4l80e trans 2wd pulled in an parked came out went to leave had no gears when shited all gears act like in neautral except park trans is not very old narrowed it to the trans fluid is ok not burnt pulled pan an filter no parts an very little on pan magnet linkage wrks there was no slipping or indication prior it ran great shifted great truck starts an runs great jus no drive gears or reversetrans is mounted in properly torque converter is bolted up and spins any help on this problem and what it could be
thanks.. steve