I can remember watching an interview with Garry Marshall. In it, he mentioned that when they wrote episodes for “Laverne and Shirley”, he and his writers would take scripts from “The Odd Couple” and re-tweak them to fit that show but then would sometimes keep the same scenes and dialogue word by word. Nobody noticed the near duplicate similarities between the “Odd Couple” and “Laverne and Shirley” apparently, lol.
There was an A-Team episode that reused a Starsky & Hutch script. In both, a main character was wounded and in danger of dying in a restaurant being controlled by a hostage taker.
A lot of episodes of The Rockford Files were reworked episodes of Maverick.