Sergeant Major Gavilanes was born on 11 July 1981 in Macas, Ecuador. Sergeant Major Gavilanes immigrated to the United States and lived in Danbury, Connecticut. He graduated from Danbury High School and enlisted in the Marine Corps on 29 January 1999. He graduated from Marine Corps Recruit Depot Parris Island, SC, In May 1999, Private First Class Gavilanes attended Marine Combat Training, Camp Geiger, NC. In July 1999, after completing Cannon Crewman Course at Fort Sill, Oklahoma. Private First Class Gavilanes was assigned to 3rd Battalion, 10th Marines, 2nd Marine Division, Camp Lejeune, NC.
He was subsequently assigned to Kilo Battery, 3rd Battalion, and 10th Marine Regiment at Camp Lejeune, North Carolina. He served as a Cannon Crewman, Assistant Section Chief, and Section Chief. He participated in several Combined Arms Exercises and Regimental, Battalion, and Battery firing exercises. Corporal Gavilanes deployed to the Mediterranean with the 26th MEU and was part of Operations Swift Freedom and Enduring Freedom.
In 2003 he was assigned to the Drill Instructor School Parris Island, South Carolina. After graduating from Drill Instructor School, Sergeant Gavilanes was assigned to 3rd battalion Mike Company and served as Drill Instructor for Lead and Follow series. Sergeant Gavilanes was reassigned to Support Battalion, Instruction training company and served as the academics instructor and testing NCOIC for the Marine Corps Recruit Depot.
In April 2006, Sergeant Gavilanes was transfer to Kilo Battery, 3rd Battalion 10th Marine Regiment at Camp Lejeune, North Carolina. He served as a Section Chief, Platoon Sergeant and Battery GySgt. During this time, he participated in numerous Desert Firing Exercises and regimental, battalion and battery training exercises, a deployment to the Mediterranean with the 26th MEU and a Deployment to Operation Iraqi Freedom 8.01 Task Force Military Police.
In March 2009, Staff Sergeant Gavilanes was transfer to the Marine Corps Information Operation Center at HQMC. As the Physiological Operation SNCOIC, Marine Corps Information Operations Center, Plans, Policies and Operations, Headquarters Marine Corps. During this time, he did numerous training exercises and Joint, Operational and Tactical deployments as PSYOP SNCOIC.
In June 2012, Staff Sergeant Gavilanes was transfer to Charlie Btry 1st Battalion 10th Marines at Camp Lejeune, North Carolina. He served as a Platoon Sergeant and Battery GySgt. He was reassigned to Head Quarters Battery to served has the Battery GySgt and 1st Sgt. Gunnery Sergeant Gavilanes during this time participated in various firing exercises, and Individual Augmented for a deployment to Afghanistan with the Mobile Strike Force.
In March 2015, Gunnery Sergeant Gavilanes was transfer to Yale University Navy Reserve Officer Training Corps. He served as the Assistant Marine Officer Instructor, during this time, he augments to the Officer Basic School for the summer augmentation program.
In May 2017, First Sergeant Gavilanes was transferred to 1st Battalion, 8th Marines. He served as the Company First Sergeant for Weapons Company and deployed to support the Unit Deploy Program 17.2. In March 2018. He was reassigned to Company A and deployed in support of Special Purpose Marine Air-Ground Task Force Crisis Response Africa 19.2 and First Sergeant Gavilanes was transferred to 2D Transportation Support Battalion to serve as the Company First Sergeant for Bravo Company.
In Feb 2022, Sergeant Major Gavilanes was frocked and transfer to Recruiting Station Springfield to serve as the Recruiting Station Sergeant Major.
Sergeant Major Gavilanes personal decorations include the Joint Commendation Medal, the Navy and Marine Corps Commendation Medal with two gold stars, the Navy and Marine Corps Achieving Medal with gold star, the Combat Action Ribbon and Drill Instructor Ribbon.