I know that "Sanford and Son" is notorious for reusing the same jokes, but I noticed one blatant reprisal of a joke on "Tyranny, Thy Name is Grady." In the scene where Lamont tells Grady he wants to do something nice for him, Grady starts crying and blowing his nose. Lamont says "Please Grady, don't do that, you might blow something out yo head that you need." A few episodes earlier, when Grady is told he can move in with Fred and Lamont, he starts crying and blowing his nose. Guess what Fred says in reply.

I noticed that too. *shrugs* I guess if it works one time, it works every time.

Also Fred and Grady both used the "I'll be a clean old man when I'm a dead old man" line