Rosco and Hogg are racing to catch the Dukes at Black Hollow with their lights flashing and siren wailing, yet in the shot where Hogg is whining about the bumpy road, the car's lights are not flashing even though the siren can still be heard.
When the Dukes are racing to Black Hollow, it's Bo in General Lee, Luke in the ice cream truck and then Uncle Jesse in the rusted truck, in that order as they pass the camera. But when Bo radios Daisy to meet them at Black Hollow, neither Luke nor Jesse are driving behind them.
When Boss Hogg and Rosco are talking in the patrol car, notice there is no rear view mirror on the windshield. After crashing into Bo in the ice cream truck, as Boss Hogg and Rosco look shocked, a rear view mirror can clearly be seen.
Multiple scenes reveal that the vehicles are missing license plates.
The splash heard when Rosco rolls down toward the pond is heard too soon; his hand is still visible in the frame, showing that he is not yet at the water's edge, and the lake is much too shallow at the edge for Rosco to make a splash from falling into it. He would merely get wet and muddy --- not to mention spluttering-mad --- from rolling into a few inches of flotsam-filled water; a loud splash would only happen if he fell from a height into water that's at least a couple feet deep.