Morton, the lone holdover from former USC coach Pete Carroll’s staff, spent the past four seasons at USC.
The 41-year-old coach previously worked with Harbaugh as an assistant with the Oakland Raiders in 2002 and 2003 and under Harbaugh at the University of San Diego in 2005.
“This is a great opportunity for John to further his career,” Kiffin said in a statement released on the team website. “We appreciate the great work he did at USC and wish him the best of luck.”
Morton originally played college football at Grand Rapids Community College and later transferred to Western Michigan. He got his start in coaching with the Raiders as a tight ends coach.
When Harbaugh was hired as coach at San Diego in 2005, Morton followed, taking the position of wide receivers coach. He also spent a year on staff for the New Orleans Saints in 2006.
In 2009, he served as the offensive coordinator for Carroll as well as wide receivers coach, before returning to passing game coordinator in 2010.
“We are delighted to continue to have 710 ESPN as our flagship radio outlet for Trojan football and men’s basketball games,” said USC athletic director Pat Haden in a statement. “As the worldwide leader in sports, the way that 710 ESPN has represented USC’s brand is consistent with the way we present it.”
Since the 2006 football season, KSPN has served as the flagship station for the USC Football Radio Network, which spans from Fresno, Calif. to San Diego. Prior to 2006, football and basketball games had aired on KMPC 1540.
Arbogast and former USC and NFL quarterback Paul McDonald will continue to serve as the play-by-play broadcast team for football, while Chris Fisher and Jim Hefner will continue to serve as basketball broadcasters for all games. The extension is scheduled to run through the 2015-16 basketball season.