He is an assistant coach in charge special teams quality control at Stephen F. Austin State University.

Having reached the pinnacle of his career as a head coach, Carthel chose to retire at age 39, and moved back to the family farm in Friona, Texas.

Trying to become a head coach again, Carthel applied for the vacant West Texas A&M job in late 2001, but athletic director Ed Harris opted for Ronnie Jones.

[2] In 2004 Carthel was named the head coach and general manager of the Amarillo Dusters in their inaugural season in the Intense Football League.

Carthel's son Colby was named head coach at Lone Star Conference rival Texas A&M-Commerce in 2013.

Colby hired Don as a quality control assistant coach in 2015 and he was on staff during the Lions' 2017 National Championship season.