As Papa Hartley and the three boys are battling it out in their trucks on the bridge the camera moves from inside the Hartley truck looking out to outside looking in. As they do this you see from the inside that the windshield in front of the driver is badly cracked but as they move to the outside angle it is not cracked at all.
During the Jamboree, a young woman is seen pushing the arm of her companion off her left shoulder two different times; it is the same scene shown twice.
When Billy Joe and Bobbie Lee are talking on the bridge and they see the pastor in his car watching them, Billy Joe turns the opposite direction to walk away across the bridge. When the pastor approaches in his car, he and Bobbie have a conversation about the dance that night that lasts a minute or two. When the pastor drives on and he stops to give Billy Joe a ride, it looks as though Billy Joe had only walked a few yards during the entire time Bobbie and the pastor were having their conversation.
During the truck fight on the bridge, the rear-view mirror on the boys' truck alternates from the position of being perfectly level to being askew several times from shot to shot.
When Bobbie Lee runs into Barksdale on the bridge at the end of the movie, it's supposed to be around 6:00am, but the sun is a full 45 degrees in the sky already.
At the dance, one of the band is playing an Ovation guitar. The movie is set in 1953 and Ovation Guitars was not founded until 1966.
The erotic magazine Bobbie Lee is reading is a more recent (1975-76) version instead of the correct 1952-53 era. This is most obvious based on the 1975 Salem Cigarette ad on the back cover.
When son James discovers the 'Bama boys at the barn dance, a fight breaks out and he pushes one of them against the truck and throws a right uppercut which is heard, but which clearly misses by about six inches.