Dixie’s Texas Tech-built drones mostly consisted of civilian vehicles upgunned to deal with the drug cartels.  A very few were actual combat designs, though the M1A5 Abrams seen in the show and movies were never part of Dixie’s arsenal.  In real life her students “recovered” some decommissioned M60 Pattons, which proved very effective against the drug cartels’ armored vehicles.  They earned her the nickname that most people know her by in fact.