Factual errors: The car that Bo finds in the water is clearly not a Dodge Charger. When he's by the door you can clearly see the door has a window frame. Dodge Chargers have frameless windows.
Revealing mistakes: When the General is pulled out of the water the flag is already painted on top, However in next scene when Luke is setting on window there is no flag on the General.
Continuity: When they take the General Lee for it's first drive you can see the back window being fine, then during the drive there's a shot of it being broken out, but when they arrive back it's whole again.
Continuity: The stains Daisy makes on the bartenders T-shirt (when she applies for a job) disappear in the next shot.
Continuity: When Luke and Bo were running away from Boss Hogg's mansion, Luke was wearing a open shirt without white t-shirt under it. You can see his bare chest. When their car was almost hit by a bulldozer, Luke was only wearing a white t-shirt.
Revealing mistakes: This movie is supposed to take place before the 2005 film. In the beginning of the 2005 film, General Lee had no confederate flag, and the 01 was sloppily painted on there. It was made to look like the original later on in the film. In this film, it says it always looked like it originally did.
Errors made by characters (possibly deliberate errors by the filmmakers): In the original series, Bo and Luke's parents supposedly died in a tragic car accident, along with Daisy's. In the film, Jesse makes many references to the boys' parents being alive.
Errors made by characters (possibly deliberate errors by the filmmakers): In the original series, Luke was the oldest, followed by Daisy, then Bo. In this film, Daisy is the oldest, and Luke is the middle.
Errors made by characters (possibly deliberate errors by the filmmakers): Near the end of the movie, Bo says, "Hopefully she'll last long enough to do what we gotta do" while referring to the General Lee. The General is always referred to as a "he", never a "she".