Hallman continued working at the college level as a position coach and coordinator for another decade, with stops at SEC schools Alabama and Mississippi State. In 2001, Hallman was the co-defensive coordinator for the Birmingham Thunderbolts in the XFL. From 2004 to 2007, he served as head coach at Muscle Shoals High School in Muscle Shoals, Alabama.
Hallman continued his career in coaching after college, working as a position coach and coordinator for another decade. He held positions at SEC schools Alabama and Mississippi State before joining the Birmingham Thunderbolts in 2001 as co-defensive coordinator of the XFL team. From 2004 to 2007, he served as head coach at Muscle Shoals High School in Alabama.