E-4,Corporal, Cpl. E-5, Sergeant, Sgt. E-6, Staff Sergeant, SSgt. E-7, Gunnery Sergeant, GySgt. What rank was Gibbs in the Marines? Gibbs' status as aGunnery Sergeant Despite the circumstances of Gibbs' departure, some NCIS fans feel it's a bit odd that after 16 years in the ...