At the beginning when Chris Vaughn asks the sheriff what happened to the former sheriff it is said that the guy was a great man but they found one day he had mysteriously skidded off a deserted road and died hitting a tree. This is a reference to how the real Buford Pusser died.
When Vaughn pulls Hamilton over and tells him to get the tail lights on his Porsche fixed, Dwayne Johnson wasn't supposed to actually strike the tail light and break it. He was supposed to "mime" breaking the tail light with his stick, with the sound effect of breaking glass to be added later in post production. But no one told Johnson this before the scene was filmed. After doing the scene, Johnson remembered that the Porsche was actually a rental car that had been rented for the day. He called to the director, "Uh, Kevin, did we just *buy* this $90,000 Porsche?" Director Kevin Bray replied through his megaphone, "Yes, thanks, Rock!"
Director Kevin Bray wanted to update the "Pusser stick" by making it a baseball bat instead of a piece of wood but there were objections, so the compromise was to just add a handle.